Cotton Weary [Liev Schrieber], now a controversial talk show host, is living a good life in Los Angeles on the fast track to fame when he's on the phone with his agent about his role in Stab 3 and other opportunities. A female fan interrupts his conversation, catering to his ego, but unfortunately Cotton learns that it's really another psycho killer Ghostface (voiced by Roger Jackson), stalking his girlfriend Christine [Kelly Rutherford] in their condo, who makes Cotton an offer he can't refuse: Christine's life or Sydney Prescott's location. Cotton doesn't accept the ultimatum and infuriates the killer into pursuant of Christine, unfortunately unable to warn her or get help from 9-1-1, and drives home erratically. Unknown to Christine or Cotton, the killer uses a voice scrambler to trick Christine in believing her boyfriend is pulling a very dangerous & horrific prank on her, chasing her around the condo with a knife while speaking in an insanely threatening manner. When Cotton finally arrives home and finds Christine in the study with a golf club ready to swing at him, he tries to explain that it's not him threatening her but Christine's so scared and doesn't believe him. Unfortunately, the killer stabs her in the back, leaving to fall to the ground dying. Cotton meanwhile struggles with the killer, losing the upper-hand and the killer stabs him in the heart, letting Cotton know it's a simple game: he just wanted to know Sydney Prescott's location. Due to Cotton's failure, the killer kills him off screen as the title comes up.
Sydney Prescott [Neve Campbell] is now living in a very secluded area of California. She has a new name, a new career with California's Women Crisis Counseling service (mostly stay at home), a golden retriever for a friend, and a sophisticated security system for the entire property around her house and presumably for all doors with double bolt locks in the house. Turning on her TV, Sydney eventually learns that Cotton was targeted and killed in his home, during the production of Stab 3: Return to Woodsborough which rattles her quite a bit.
Gale Weathers [Courtney Cox] is now with Total Entertainment and providing a lecture at GW Bestor Series School of Journalism when she's informed by Detective Mark Kincaid [Patrick Dempsey] that Cotton Weary was killed and a younger photo of Sydney's mother Maureen Prescott was found on Cotton's body.
On the set of Stab 3, Director Roman Bridger [Scott Foley], Producer John Milton [Lance Hendricksen], and a studio executive contemplate the decision to continue production or cancel it with Cotton's death on everyone's mind including the press & the public. Violence & cinema are raised as questions, but from Roman's point of view it wasn't his idea to allow Cotton in the movie; that was the studio's. Milton said 35 years in the business; this is 1st time he's had a psycho and asks Kincaid's partner Detective Wallace [Josh Pais] about the connection between Cotton's death and the movie. Wallace suggests the obvious: "Movie's called Stab; he was stabbed."
Also, on the set, we're introduced to Stab 3 actors Tyson Fox [Deon Richmond] playing Ricky from the video store (Randy), Tom Prinze [Matt Kesslar] playing another version of Dewey, Sarah Darling [Jenny McCarthy] playing Candy, and Angelina Tyler [Emily Mortimer] as another version of Sydney while they discuss Cotton's death & the production of the movie as well. Tyson & Angelina are worried about their futures as actors, while Tom mocks them & Sydney and wants to continue production no matter what cost. Sarah looks at them, thinking about the points made and continues reading her script.
Gale finally shows up on the set, a Woodsboro replica, meets her twin Jennifer Jolie, a huge fan obsessed with her Gale character and learns Dewey's a technical advisor for Tom, guard, and clearly Jen's love interest. Dewey thinks Gale's back for the action and the story once again. Tom's ticked off about Gale's smear job on some accident he had, which she admits was her way to boost ratings at his expense. Milton sees Gale & Dewey talking and kicks her off set and as she exits the set, Jay & Silent Bob actors Jason Mewes & Kevin Smith recognize Gale and make a sarcastic remark to which Gale gives Jason the bird.
Neil Prescott [Lawrence Hecht] visits his daughter at her place. Sydney naturally wishes the recent events never happened and if only her mother's past was different, life be easier. Neil asks her to come home, but Sydney defends her exiled lifestyle stating at least she can't be targeted again if they can't find her. In the next shot that night, Sydney's sleeping on her couch while her mother in a nightgown walks up to the house. Sydney opens her eyes to see her mom, staring at Sydney through the window, calling her name and talking to her hauntingly, and claws at the window before sliding down leaving blood streaks from her fingernails. Sydney gets up for a closer look and Ghostface pops in the window, says hello, and knocks the window out with a knife, startling Sydney and knocking her back on the couch turning away from the window. The dog wakes up as Sydney turns toward the window and realizes it was just a hallucination.
Sarah meanwhile drives up to the Stab 3 set to meet Roman, the director, to run lines. While waiting for him, Sarah is startled by Tyson and Stan, the make-up artist. Tyson hasn't seen Roman, but Sarah waits in his office and jumps when Roman calls his office to let Sarah know he's late. Sarah's not happy with her part, but Roman says they should run lines anyway. As they go through Sarah's lines, Roman supposedly changes the name of Sarah's part to her real name in mid-script and Sarah asks if there's been another script change. Roman lets her know it's a whole new movie and Sarah's the star to be skewed like a pig. Horrified, Sarah runs out to the studio exit, seeing a shadow thinking it's the killer (really just a guard locking up) continues on through the building and hides into the costume room, calls 9-1-1 only to discover the killer has been there the whole time and begins attacking Sarah but misses. He chases her into a storage area, smacks her through a door window, and stabs her in the back.
Gale & Dewey meet for lunch, discussing their relationship the last few years and Dewey's frustrated while Gale recognizes they're different. Gale suggests there's connection for sure between Cotton & Sydney, to which Dewey said a couple months back someone did try to get Sydney's case file and dispatch declined, so the records were broken into but Dewey had removed Sydney's before the thief could get it. Jennifer calls Dewey to come to her house and Gale comes along.
At Jen's house, she's all worked up about Sarah's death and we meet Steven Stone [Patrick Warburton], Jen's bodyguard. Gale is astonished when Jen and Dewey agree the two murders are in the same order as the script. Gale's the third or Jennifer whichever. Dewey grabs a flashlight from his trailer and is confronted by Steven who wants to run the protection detail. Dewey's unphased.
At Stab 3 set, Kincaid & Wallace discuss Sarah's murder and find Gale there asking them questions about the crime scene and Dewey discloses Jennifer is next to get killed since she's Gale. Kincaid suggests that there's actually 3 scripts going around, so there's no actual guarantee that Jennifer is next, plus Steven's watching over her so she should be fine. Roman is worried about production and is getting more heat from the studio as Sarah's death puts another damper on his production getting done and making deadline. Kincaid walks over to him letting him know Sarah was supposed to meet with him, which Roman denies even calling her. Wallace insists Sarah's roommate recognized Roman's voice, to which Roman says there's a conspiracy out to shut down his movie. Kincaid & Wallace walk Roman down to the station.
Sydney's at home continuing to handle her crisis counseling calls when a female caller notifies Sydney that the caller killed someone. Sydney says she should be calling the police, to which the caller's voice insists she should be calling Sydney. It's the killer using Maureen Prescott's voice haunting Sydney and asking her to turn on the news. Sarah's death is announced to which the killer's raspy voice comes and asks Sydney if she thinks this whole thing is over. Sydney, gun in hand, looks around her house looking for the killer and looks out her window, but no Ghostface.
Steven's patrolling Jen's grounds and thinks he might have heard something. Inside, Tom's ripping the crappy parts out of Stab 3, being a little sarcastic about the murders, which scares Angelina who thinks Tom's drunk because he's being a jerk and leaves the room. Tom makes a rude remark about Angelina stepping on her competitors' toes before she got the Sydney part. Jen looks at him thinking Tom made a move on Angelina and she wasn't interested. Tom denies & Jen looks at him in disbelief and has Dewey escort her to another section of the house while Tom continues ripping things up. Gale arrives at the house and starts spying on Jen & Dewey's private conversation about Gate, getting caught by Steven, who notifies Dewey to Gale's presence. Gale suggests Sarah's call was from a cloned cell phone, not Roman's. Gale talks to him about Maureen Prescott's past that there wasn't many records on Maureen Prescott when she was young. Dewey recognizes the background of Maureen's older picture and finds Jen's background is the same which concludes Maureen was an actress years ago and worked at Samoine Studios (where Stab 3 is shot).
Steven's in Dewey's trailer when Dewey calls him and asks him to watch Jen as something has happened. Steven is dismissive since he doesn't work for Dewey and makes a crude remark about Dewey's sister, which pisses Dewey off. However, it's not really Dewey at the other line, but the killer who's pissed off and runs from a hiding spot in the trailer at Steven and stabs him in the back.
Dewey meanwhile suggests there's an even bigger connection now between Maureen Prescott & Stab 3 and dials Kincaid when Gale looks around Jen's house and notices it's a little quiet than normal. Suddenly, the door opens but no one enters and we notice it's really just wind blowing from outside. Dewey calls for Angelina & Tom, but no response. Suddenly Jen enters the house, scaring Dewey who draws his weapon & points before recognizing Jen. Tom pops up with Angelina and Dewey points, but doesn't shoot. As Dewey puts his gun away, he looks outside one of the open doors as everyone suddenly has their attention on Steven in a zombie walk, bloodied from ears & mouth with a knife in his back trying to communicate but falls. While the others' eyes widen in horror, Dewey runs over to attend to him.
Realizing the killer could be anywhere near them, Dewey instructs everyone back inside the house just as the power goes out. Frantic, everyone begins to get rattled at every noise heard, including when a phone rings and everyone's checking to see whose it is. Jen realizes it's a fax from the killer and grabs a flashlight to read it, written from the Stab 3's script reading like a riddle. Suddenly another passage, much like the first with characters in other scenarios, and ends in "the killer will give mercy to...." just like the first. Unsure what to do, everyone runs outside. Frustrated, Tom decides to go inside while everyone runs from the house. He reads another fax in the dark, ending with "the killer will give mercy to whomever...." He lights a lighter and reads that it ends in "whomever smells gas." Next shot, he's immediately engulfed in flame, only screaming for a second or two, as everyone watches in horror and run from the house as it explodes killing Tom.
The humongous fireball erupts forcing the survivors to jump over a railing from Jen's patio and land on a steep dirty hill, rolling down and landing in various flat areas over several yards in the back of the property. The movie follows Dewey as he gets up, looks around and can't see where everyone else went, & calls for Gale & Jennifer and they reply back (off-screen) from a far distance. Dewey looks for Gale, sees her down at the bottom of the hill standing on the road near an SUV. Before the killer is able to attack Gale from behind, Dewey shoots the killer, to which the killer rolls under the SUV and disappears. Meanwhile, not careful of his footing while firing his weapon, Dewey looses his balance and falls down the hill next to the SUV and joins Gale looking for the killer. Gale thanks Dewey for saving her and they're about to kiss when Jen shows up, freaking out wondering where was Dewey in protecting her and slugs him. Gale turns and immediately punches Jen in the mouth, causing Jen to fall to the ground. Jen turns and suggests she's ready to sue (her lawyer going to love Gale's assault on Jen). Gale feels much better though, considering Jen was being a bitch. They hear a noise and turn to their right seeing Angelina, walking toward them, almost in shock, frightened and mourning Tom's death asking if they're safe for now. Dewey suggests they're fine now. Dewey, remembering the killer had rolled under the SUV, looks under the SUV finding another picture of Maureen Prescott, on the back a message, "I killed her."
At the LAPD office, Gale and Dewey meet with Kincaid and discuss this latest development. Gale suggests they know Billy Loomis and Stu Monker killed Maureen Prescott and went in grave detail about it to Sydney from the first movie. Kincaid suggests Sydney was wrong before, maybe this is from the real killer. Frustrated with the situation, Kincaid & Wallace need answers since there's three dead celebrities, a bodyguard, and now the mayor isn't happy with this threat & the press it's receiving. Gale asks the question: What does Stab 3 and Maureen Prescott have in common? Where's the link? Kincaid suggests well Maureen's picture is at the same studio as Stab 3 is shooting from. Kincaid suggests Sydney might know since she knows her mother and Dewey suggests her father was married to Maureen and he doesn't know much either. Kincaid and Wallace feel the pressure & are ready to interrogate Dewey, who feels of course on the spot & at the gallows. Gale diffuses the argument, to which Kincaid insists they bring Sydney in or Gale and Dewey will be charged with obstruction of justice.
Dewey calls Sydney and begins leaving a message when he sees Sydney has come in to LAPD, hanging up to greet her. They catch up and talk a little about Gale. Sydney asks what's going on and wants to meet with Kincaid. Dewey confronts her for coming out of the cold, but Sydney responds that the killer contacted her home phone, realizing it's only a matter of time before her isolated life won't feel so safe anymore. Sydney rather joins Dewey and Gale to solve this mystery. Dewey introduces Kincaid to Sydney and lets Kincaid and Gale know the killer called Sydney. Sydney suggests that it was the same old bullshit, catching up & how she wants to die. While Kincaid, Gale & Dewey discuss leads, Sydney looks at her mother's pictures on Kincaid's wall. Kincaid informs her that the killer is leaving these pictures at every murder site and asks about the connection. Gale asks her whether Maureen was an actress or a model years ago, since the background in Maureen's shots match Jen's in the studio. Sydney suggests to Kincaid she's ready to visit Stab 3 set.
Just when Sydney, Dewey, Gale, Kincaid and Wallace arrive to enter the set, Randy Meek's little sister Martha [Heather Matarazzo] walks out and scares them. Dewey prevents Wallace and two uniform officers from shooting the young girl, since Sydney & Dewey know her. Martha suggests she misses them not being in Woodsborough and shows them a videotape they need to see. It's Randy back at Windsor College during the time of Scream 2 a few years ago, leaving his legacy by acknowledging it's possible he won't make it out and that the killer may come back for a third time. Sydney is really surprised at how Randy prepared for a third sequel vs. the third & final chapter in a trilogy. Randy's sure the past is now a clean slate, different than what everyone knew before, and warns Sydney that in a trilogy as the main character in this live horror trilogy Sydney's destined to die in the end. This 3rd round could be a bloodbath like Reservoir Dogs before it's over. Randy wishes them well and suggests to the group that he might see them soon because some may not make it out alive. Sydney and Dewey hug Martha goodbye and Martha leaves.
Gale takes a walk around the studio and tries to open a door but needs a key to get in. Jen approaches her which freaks her out. Using Jen's pass key, they enter the studio and meet Bianca [Carrie Fisher], the studio's bitter records coordinator. For an inside joke, Gale asks her if she's Carrie Fisher and Bianca says she isn't and suggests that Carrie Fisher slept with George Lucas to get the part of Leia in the Star Wars trilogy. Jen is astonished at how familiar they look (done for comedic effect of course). Gale apologizes and asks for information on Maureen. Bianca resists initially for a $50 bribe Gale offers, but Jen takes a step further and offers one of her expensive jewelry valued at $2,000, next shot Bianca's pulling a file on Maureen Prescott's stage name Reina Reynolds. Gale reviews the file which enlists all of Reina's films, some directed by John Milton, the producer of Stab 3, raisinh Gale's and Jen's eyebrows.
Hanging around the Stab 3 set, Sydney is washing her hands in the bathroom when she hears a clang in the stalls behind her which rattles her a little and tries to get a grip until she hears another. Just like in the first movie, she looks underneath only to see boots stepping off the floor to stand on the toilet seat. She arms herself with pepper spray and kicks in the stall door to find Angelina Tyler. Angelina is startled by Sydney's assault on the door at first, but immediately recognizes her. Feeling bummed out that production is shut down due to the murders and convinced that her career is likely over, Angelina grabbed some souvenirs to remember Hollywood by. Feeling sympathetic about Sydney's past & current ordeal, Angelina states it was a great opportunity and she wanted to do right by Sydney. Sydney sighs and says Angelina probably would have. Unusually wound up, Angelina is amazed as the target of her portrayal is right there and wished she finished production. Angelina collects, with Sydney's help, the memorabilia, leaves the bathroom and heads out of the studio. Sydney finds Angelina left something on the floor in the stall and exists the bathroom only to see Angelina's gone.
Sydney looks around and heads down a hallway which leads to the set, feeling a little nostalgic while looking to see if anyone else is there. She continues walking around the set and enters her "pretend" house and "bedroom." This brings back happier memories of her conversation with her ex boyfriend Billy before he became a Ghostface psycho. She then hears a noise looking outside her "fake bedroom window" but doesn't see anything. Behind her a door closes startling her, so she opens the closet door and adjoins them which forces both doors to flex a little (just a draft) as Sydney gets rattled. She backs away from the doors, thinking the killer is coming only to discover Ghostface appears in the window behind her and pulls her out of the bedroom onto the set floor. Sydney manages to escape and goes inside another house, where Ghostface appears and chases Sydney up the stairs. Sydney frantically slows the killer down and runs up a couple floors, calling for Dewey to get on the set. Hearing a voice from another room, Sydney's curiosity brings her to her mother's death scene. Scared and upset, she hears more voices and sees on the floor a fake cadaver covered by a white sheet with blood spots on it. The voices of her mother, Stu, & Billy seem to be coming from it. She runs toward the window and continues to hear her mother's voice as she turns to see the sheet has rose with her mother's haunting voice. Sydney jumps out of the window calling for Dewey and somersaults onto the set floor.
Lights turn on as Dewey, Wallace, and some police officers rush in from a set door to Sydney, who's crying by now and informs them the killer is upstairs in the fake house. Dewey said Sydney shouldn't have been up there, since that's the production preparation for Maureen's dead scene. Wallace and some officers go up there to check it out, but the killer has vanished. Angelina and Tyson walk in to find out what happened while Kincaid rushes in to Sydney's side. Wallace interrogates Angelina and Tyson and question Angelina about the stalker mask she took for memorabilia. Kincaid confronts Sydney about seeing the killer on the set and Sydney swears he was there in "Woodsborough" (on the set). Kincaid reminds her it's just a set, not the real thing, which Sydney acknowledges but insists someone in a Ghostface costume was stalking her on the set. Dewey comforts her and suggests everyone believes her, as does Kincaid who drives Sydney back to the precinct for her protection while they figure out what's going on and who's trying to get to her. Jen and Gale walk over to Dewey and confirm Maureen Prescott, under the stage name Reina Reynolds, was an actress working for, none than, John Milton, Stab 3's producer at the studio.
Roman is having a lengthy argument with Milton in the latter's office about the reason behind these murders and the fact it's happening while Stab 3's in production. They are interrupted by Jen, Gale, and Dewey who want to know what the hell Milton and Reina Reynold's history is. Roman asks them who Reina Reynolds is, but Milton suggests Roman should concern himself with his birthday party and not to cut the cake without Milton. Jen realizes it's Roman's birthday and wishes him "Happy Birthday." Disgusted with his bad luck, Roman suggests as if he doesn't had enough problems he has to celebrate his birthday and leaves the office. Dewey confronts Milton about knowing Reina Reynolds/Maureen Prescott and Milton acts like he doesn't know anything, until Dewey says he'll give Kincaid a call if he doesn't get a straight answer. Milton acknowledges he knows Reina Reynolds. Jen, breaking into her overly hyped Gale Weathers shtick, confronts Milton about making money off Reynolds/Prescott's death, and accuses him of being obsessed with Maureen and her daughter Sydney. Gale settles Jen with humor calling her "Geraldo", no doubt for Geraldo Rivera, famous for that type of reporting for money and ratings. Milton suggests Stab wasn't his idea and making the film he realizes he knew Maureen Prescott as Reina. He knew the controversy behind the murder and was worried about the press because he knew the victim, but Gale doesn't buy it and presses him about their history. Milton acknowledges Reina was working for him, was invited to a lot of his parties, and was desperate to make something of herself. Gale asks him if Reina was possibly attacked. Milton acknowledges things got out of hand and maybe some producers and directors took advantage of Reina and that maybe Reina wasn't cut out for Hollywood. He also acknowledges no charges were brought. Milton felt Reina couldn't play by the rules and that's why she didn't last in Hollywood.
Sydney and Kincaid meanwhile talk about movie trilogies, his job, Sydney's ghosts (as Kincaid does get them too - hazard of the trade unfortunately), and about Maureen Prescott. Kincaid confirms Sydney's most likely telling the truth about Ghostface on set, which is good news because if this killer was there, then there's two ways to take them down: catch 'em or kill 'em, just like every other bad guy Kincaid dealt with. Sydney asks him what's his favorite scary movie, to which Kincaid responds his life is the most horrific and Sydney concurs as she been there the past 4-5 years.
Dewey, Gale, and Jen meanwhile are returning back to the precinct to talk to Sydney and Kincaid about what they found when Dewey receives a phone call from Sydney while driving, suggesting that Milton supposedly called her to come over to his mansion to give Sydney some information. Dewey suggests it's not safe for Sydney to be out there, but Sydney suggests Kincaid is with her. They arrive at Milton's place and are greeted by birthday boy Roman and ask him where Sydney is. He says she's in the mansion and leads them inside, only to find out that he really means Angelina, the actress who plays Sydney in Stab 3. Tyson is also there as well sitting on Milton's couch. Gale confirms she means Sydney Prescott and Roman suggests that he would have never invited her here, but Gale suggests Sydney's coming which Roman doesn't mind.
Roman suggests he wants to walk around the Milton mansion, but Tyson confronts him with the idea that a killer is on the loose and whenever Dewey for example is confronted in one of these situations he's left as a shishkabob. Jen volunteers to walk around the place with Roman and they head to the basement which scares Jen, who watches Roman go down the stairs in bad lighting. Tyson and Angelina go up stairs and look at the various posters Milton produced and posted on his walls. Roman seeks a coffin in the basement and opens to find a fake skeleton with eyeballs in its sockets. It's a little scary to him but he manages. He hears a noise behind him and looks over while Jen calls him from up the stairs and hears a clanging sound for a couple seconds, but no Roman.
Dewey and Gale are concerned about why Sydney hasn't showed up, so they recheck the phone call they received by dialing it and hear the ring tone in a closet within the living area, turn on the light to see the phone, the voice scrambler which has everyone's voices, and a Ghostface mask, implying the killer is at the mansion. Dewey arms Gale with a gun and they split up in different areas of the house, calling for the others. Dewey finds Tyson and informs him that Stab 3's back in production (the killer's on the hunt to kill off characters for real once more). Gale finds the basement door and calls for Roman and Jen, then goes down to the basement, opens the coffin, and finds Roman dead with a knife in his chest. This naturally sets Gale back and bumps into Jen, which gives them both a jump.
Gale and Jen run upstairs looking for Dewey and find Angelina. They inform her Roman's dead. Angelina wants to leave, but Gale and Jen want to find the others. Angelina confirms she slept with Milton to get Sydney's part and doesn't want to die in vain with Gale and Jen. Dewey calls Gale from another room while Angelina panicking continues to run down the hallway, makes a right, and another left and runs right into the killer who stabs her to death. Gale and Jen hear Angelina's blood curdling scream and run down the same pathway and find her down stairs being dragged off screen.
Gale and Jen finally run into Dewey and informs him Roman and Angelina are dead, just then the killer gets the drop on them and punches Dewey in the head. Gale and Jen run into the bedroom and find Tyson, while the killer tracks them down and pushes Tyson away. Dewey confronts the killer, gets slashed in the arm and punched again. Tyson gets physical with the killer and is stabbed in the abdomen. Jen decides to hide in the bathroom while Gale picks up a vase and throws it at the killer. Tyson is able to get up and run, yelling help and police (like anyone would hear it inside a closed windowed house). The killer, realizing he's still mobile, chases after Tyson and catches up with him, throwing him into a vase case, and out an open window with a balcony onto the brick patio killing Tyson as his head smacks against the pavement.
Jen finds Milton's secret passage way in the house and walks down some steps, only to find the killer has as well and chases her up the stairs. Running from the killer, in the passage way, Jen finds Dewey in the bedroom and begins knocking on the tinted windows trying to get his attention, so he realizes someone's back there. The killer finally catches up and attacks her as Gale joins Dewey and they realize the mirrors are shaking, so Dewey begins shooting them out one at a time, only to realize by the last one Jen falls to her death through the broken window pane as Ghostface had already killed her and disappears.
Dewey and Gale go back to the main section of the hallway and can't find Sydney who hasn't arrived yet. Meanwhile the killer attacks Gale while Dewey's away and they struggle right just outside the kitchen at the basement entrance to the house and falling backward through the open door and down the steps. Knocked out the killer lands on the bottom step while Gale is down on the basement floor and manages to get up only to realize the killer is in between her and her means of escaping. Dewey walks outside in the common area finding Tyson dead on the bricks and calls for Gale. From the basement, Gale hears him calling while the killer has a little reflex but not enough strength to wake up and passes out. Upstairs, Dewey receives a call from Gale downstairs, asking him to open the basement door, but is instantly suspicious since he fears the killer is once again using her voice to attract his attention. Gale insists it's really her speaking and he should just open the door. The killer finally wakes up at the bottom, just as Dewey opens the door and truthfully it was Gale talking him. Dewey tries to shoot the killer before Gale is attacked, but realizes he doesn't have any bullets, so the killer throws his knife up the steps at Dewey and luckily the handle part is the one that hits Dewey in the head, causing him to lose his balance and fall down the steps. Gale attends to him, while the killer flashes his knife standing before them.
At the police station, everyone's working 2nd shift and Sydney's still in Kincaid's office, foot on the desk bored, confirming it was the killer who called Dewey and sent him, Gale, and Jen down to Milton's. She happens to see her file on Kincaid's desk and opens it to see dozens of articles, forms, and news clippings about the past 4 years from Maureen's death to now. She receives a call and hears herself like an echo. It's really the killer with the voice scrambler, who changes to his normal raspy voice and suggests that he has Gale and Dewey and wants Sydney at Milton's place ASAP. Sydney immediately wants to attract Kincaid's attention to the call, but the killer lets her know it's not happening and if she does, she won't see her friends alive again. She says "Where?" to which the killer says he'll let her know when she's on the road.
Sydney opens Kincaid's drawer and grabs his backup gun. When Sydney arrives at the mansion, she checks on Tyson and realizes he's dead and looks around, just as the killer calls her and asks she run the metal detector over her body, which beeps at her ankle. The killer insists she remove the gun and throw it in the pool which Sydney does. The killer insists she join the party inside, which she suggests that she won't, but he keeps saying that Dewey and Gale are right inside and she should take a look. Gale and Dewey are hogtied and Sydney walks over to them and starts working on releasing Dewey and Gale from being taped up. Just then Ghostface creeps up behind Sydney as she turns and smacks her across the face and she falls. He's ready to stab her when she draws Kincaid's gun, pointing it at the killer and shoots a few shots. Sydney continues to start untaping Gale and Dewey and Gale looks up at where Ghostface fell and notices the masked killer's no longer there. Sydney looks over and sees that the killer's missing too and grabs the gun and looking around.
Kincaid shows up, only to discover Sydney becomes suspicious of the fact he's alone and doesn't trust him. Diffusing the fear and intensity in Sydney's eyes, Kincaid withdraws his weapon to show good faith and calm her down. Ghostface pops out of nowhere, knocks out Sydney, and attacks Kincaid struggling with him, knife in hand, and Kincaid manages to overpower him, but not before the killer kicks him in the stomach and Kincaid loses balances, hits his head on the mantle of the fireplace, and falls to the ground. Sydney manages to get up and fires the gun at the killer who ducts, tries to fire again but the gun's out of bullets, so she throws it away and challenges the killer to chase after her. The killer draws his knife and lunges at her. Sydney manages to move out of his path and the killer falls through the window while Sydney runs down the main hallway, with the killer back up in hot pursuit. She runs into Milton's study, locks the door, and looks for a secret passage way access on the bookcases which she finds and enters Milton's private study, locking the door to the exit back. Sydney sees a movie on a screen of her mother and can hear her mother's voice, which again turns out to be the killer in the same white sheet with blood stains on it from the set. Upset, Sydney tries to escape but the killer locks up the safe room.
The killer lays out the truth. She asks who he is, to which he informs her he's the other half of her - her sibling, in short. In his raspy voice, the killer tells her he searched for a mother too, an actress named Reina Reynolds, and when he finally tracked her down she turned him away, saying that she had a new life and a new name, that Reina doesn't exist anymore, and Sydney was the only child Maureen claimed. The killer suggests she wouldn't acknowledge her son, as he takes off his mask, revealing the killer to be Stab 3 Director Roman Bridger, back from the dead. Roman continues his story about how Maureen said Roman was Reina's child and Reina's dead, so he figured if Reina's truly dead, he'll make it real and begins stalking her, filming her every move, making a movie which shows the good and bad of Maureen Prescott. Roman talks about how Maureen was sleeping around, mentions Cotton which everybody knew, but then Billy's father - that's what he needed. He showed the film to Billy, which motivated and coached Billy on how to solve both their problems with a few tips including a partner (Stu), find someone to frame (Cotton), almost as if Billy was making the movie. Sydney concludes that Roman was responsible for everything the last 4 years, to which he suggests that he's a director, he directs, meaning he knows what sequence he wants for anything and will go through several organized plans to make it happen whether preparing for a scene or seeing someone executed premeditated. Roman informs Sydney he had no idea that Gale would write the book and the studio would make a movie about it, but is quite fascinated with the idea until he realizes they portrayed Sydney as the victim and the star of the movie which clearly pissed him off.
Dewey finally gets loose, helps Gale, and they attend to Kincaid who's still managing and hands Dewey a gun and tells him to get the killer. Dewey and Gale start trying to break into the study with great success. Sydney acknowledges Roman's plan succeeded and the showdown shall continue with the villain Roman dying at Sydney's hand. Roman corrects her saying he's not the villain and Sydney is so she'll be no longer. He also reveals to her the hogtied Milton, suggests how Milton and his posse attacked Reina/Maureen, messed her up, made her a whore, and asks if Sydney hates Milton for what he did. Roman shows her he recorded a message he created using Sydney's voice threatening Milton. Milton attempts to bribe and beg Roman to spare his life. Roman slits his throat, while Sydney snaps and throws the responsibility on Roman who continues his rendition on how he intends to have Sydney framed for the murder and the other murders. Roman truly believes he's going to get away with this as he lays out why Sydney supposedly does the crimes. Sydney cuts him off, informing him the truth is that he's a whack job like every other she dealt with and he's responsible for his own actions, which Roman clearly can't handle facing the idea that she's right and he's going down. He gets pissed, have a loud argument, and Sydney and Roman begin to struggle.
Meanwhile, Dewey and Gale look for a way inside the safe room, finally shorting the safe lock and the lights. Kincaid using a couple pins finds his own way in, opening another door and asks Sydney where the killer is. Unfortunately, Roman gets the drop on Kincaid and knocks him out. Roman looks over the cop, withdrawing Kincaid's weapon and make sure there isn't another weapon on him. Sydney grabs Roman's knife and confronts him, to which Roman responds that he has a gun and shoots her in the abdomen. He walks up to her and shoots in the chest and she passes out, supposedly dying. Roman grabs his knife as he hears Dewey and Gale calling for Sydney and threatening him if he harms her. While locking the other exit, he turns to Sydney only to discover she's missing. Off screen, she grabs an ice pick while Roman searches for her, flipping out that the same game he's playing is played on him while hearing that Dewey and Gale continue their efforts to unlock the door to the safe room. Roman decides to call Sydney's phone as a means to track her down, which works as it rings very close by. All of a sudden Sydney jumps out from behind the bar and stabs Roman who falls and turns toward her suggesting he thought he killed her. Sydney reveals she's wearing an LAPD standard issued bullet vest, Roman is amused, and Sydney concludes they must think alike and stabs Roman in the chest. Finally, Dewey and Gale bust into the safe room and see Sydney, kneeling over Roman, who's dressed in black cloak, stabbed, realizing that he was Ghostface this time around. Gale tends to Kincaid, who's wounded but still fine, while Dewey keeps a gun pointed on Roman. Roman reaches out to Sydney to hold her hand as he's supposedly dying. Dewey suggests she be careful since the killer always generally comes back for one last scare in a horror movie. Sydney suggests this isn't a movie at all, and low & behold Roman gets up, grabs a knife, starts screaming like a maniac, lunging at them, and Dewey fires his into Roman's chest, but to no avail apparently Roman definitely has his own vest and manages to stop the bullets before they reach his body. Sydney realizes this and yells to Dewey to shoot him in the head, which Dewey finally registers and shoots Roman point blank, killing him. Dewey thanks Sydney for her help as they look at Roman.
At Sydney's house in secluded California, Dewey and Gale visit and look at the beautiful landscape from the house and watch Sydney walking back up to the property with her dog once more. Dewey asks Gale to sign "The Woodsborough Murders", which Gale thought he hated, but he asks her so she opens the book's cover to realize it's just a fake book to disguise Dewey's engagement ring and he proposes. After some consideration of their differences and their time slots, Gale accepts and they kiss.
Sydney opens up the gate, but noticeably doesn't close it and punch the code. At the house, she enters and is ready to arm the security system, but stops herself, debating on whether to let herself continue to live a controlled paranoid life or to live a little and take a chance. She chooses the latter as Kincaid, with arm in sling, walks in to greet her with popcorn and invites her for a movie in the living room. Sydney asks what kind of movie, to which Kincaid suggests she has to find out for herself as Dewey and Gale walk in too and have a seat. Sydney sighs and walks in when she hears the door open behind her and turns around to watch it swing open and wait for a sign that someone's after her, but nothing, only the wind blowing. Sydney turns and just grabs a seat and the screen goes back as the credits begin to roll.