The opening shot is in Mumabi, India. A busy market street leads to a restaurant where a married couple Maria (Sarah Wayne Callies) and Michael (Jeremy Sisto) are talking about his job. Maria surprises Michael telling him she's pregnant.
Later, on a beach, Maria tells Michael that she finds the place wonderful. Michael asks if she is open to living in Mumabi and starting their family there. Maria asks if he is sure, and Michael notes that he would have to come to Mumabi several times a year anyway. Maria happily says "yes". A small child comes up to them and Michael asks the child something in the Marathi language. Maria asks him to translate what he said. Michael said he asked the child if they should stay here forever. The child looks at Maria and it's mouth opens to bellow a loud, demonic scream.....
Maria wakes up startled. It was just a bad dream. Six years have now passed. Maria looks at her husband, who is still sleeping. Rage overcomes her and she begins to hit him, jostling him awake. He grabs her arms to stop her, which leads to him comforting her as she breaks down in tears. The camera pans to a family photo; Michael, Maria and their two children, Oliver (Logan Crenan) and Lucy (Sofia Rosinsky). It is clear a heartbreaking tragedy has occurred to the family.
The next morning, we see Lucy with the family dog, Winston. Michael and Maria have a housekeeper/nanny Piki (Suchitra Pillai-Malik) as well, who helps make breakfast. It is clear now that Oliver has died some time back.
After breakfast, Maria apologizes to her husband for the night before, saying she feels so lost. Michael says they are going to get through it as he heads out for the day. Piki, from the doorway, sees the distraught Maria.
That night, Michael comes home. He sees Piki, who explains Maria is already in bed because she had a migraine. He goes to check on Lucy, kissing her forehead. As he leaves the room, he hears voices. Going into his bedroom, he realizes his wife fell asleep watching old home movies of the kids. Oliver and Lucy are on the piano, playing a piece together. Michael, holding the camera, congratulates them for doing so well. Michael, usually having to be the source of strength for his wife and daughter, is overcome with emotion and bursts into tears thinking about his son. He shuts the TV off and kisses Maria's forehead. Were going to get through this, he says to himself. Noticing something in the sheets, Michael moves them, only for a pill bottle to fall to the ground. Michael realizes that Maria has attempted suicide and calls emergency services.
Michael is in the ambulance with a barely conscious Maria. In her stupor, she recalls the accident that killed her son. A traffic accident has caused them to drive off the road into a large body of water. The car was filling up with water and Maria was having trouble making an escape route. Oliver was screaming because his leg was stuck and he couldn't get out. Meanwhile, Maria notices Lucy is unconscious and unbuckles her seatbelt as Oliver continues to plead for his mom to help him. The car is quickly filling up with water and she cannot free him. Maria tells Oliver she is so sorry. We next see her escaping the car with Lucy and gets to shore. As she screams for someone to help her son, she is restrained by several men who possibly cant understand her (or realize that is impossible to save the boy at that point). Maria is inconsolable.
At the hospital, Michael is met by Maria's doctor who says she will be fine though she took many pills. Maria, in her room, wakes up to see Piki, who tells her shes lucky to be alive. I just cant bear life without him, Maria says. Piki goes on to tell Maria that she once had a daughter who drowned falling into a pond when Piki wasnt watching her for just a moment. Piki asks if Maria wants one chance to say a final goodbye to her son.
Piki explains she lived in a small village, and in that village, there is an abandoned temple where it is said the line between the living and the dead is very thin. Maria would have to take her sons ashes and spread them on the temple steps, then lock herself in. When night falls, Oliver's spirit will come to speak to her one final time. Michael comes into the room, interrupting Piki. Piki says she will give them some time alone. Michael embraces his wife, who cries and tells him how sorry she is.
Back at home, Maria watches Piki as she prays for her daughter at a shrine. Piki turns around and sees her. Piki says if she helps Maria say goodbye, she must promise one thing. When Oliver begins to speak, no matter what happens, no matter what he says or pleads, Maria is NOT to open the temple door for any reason. Maria promises she will not.
That night, Maria and Piki with a crew exhume Oliver's body. Maria refuses to look at the casket but cant help but look when they begin to open it. Piki tells her not to look as his body has decayed considerably since his death. However, Maria spots Oliver's tiger Khan (who was buried with him) and picks him up. Unfortunately for her, it was gripped in Oliver's decomposing hand which horrifies her.
The work crew burn Oliver's body while Piki and Maria watch. Maria notices a few strange men nearby, covered in ash and chanting. Piki explains that they are local shamans who coat themselves in the ashes of the dead and even consume the flesh of the deceased in order to strengthen their bonds between the two worlds.
Piki takes Maria to the train station the next day and tells her when to get off. Maria is worried about what her husband will think, but Piki tells her she will cover for her. As she travels, we hear narration of Maria, apparently a voicemail in which she tells Michael not to worry. She needed a few days away to get better, and to be ready to let go of their son.
Maria takes a taxi to the village. As she looks around the isolated area, two local women stare at her. Maria heads into the forest, having to walk far. She finally finds the decayed temple, grimacing at the numerous dead birds and other animals strewn around the area. She also notices the unmistakable silence of the surroundings.
On the steps, she pulls out Oliver's ashes, stored in a small box. I love you so much, Maria says, before dumping them on the stairs. She goes into the temple and locks the door. She then sits down and waits for night to fall. Hours pass, so she begins to look around. A few birds fly out of nowhere, scaring her. However, she begins to really be freaked out when she sees that they drop dead and rapidly decompose moments later. In addition, she discovers what appears to be a mummified corpse of a woman. It is at that point that Maria realizes she made a mistake and goes to leave. As she is about to, she begins to hear things. The door rumbles and tries to open. She hears the voices of men. Then, as if by a miracle, she hears the voice of Oliver.
Maria asks if it is really him, which Oliver affirms. Maria breaks down and cries, telling Oliver that she is so sorry for leaving him. Oliver asks where he is. Maria tries to tell him that he died and she is here to say goodbye. Oliver pleads for her to open the door. Maria says she cant. Oliver continues to plead then says someone is taking him and he has to go. Maria cant believe it, seeing as they only had a moment to speak and in a misguided panic, opens the door despite Pikis warning, and screams Oliver's name but no one is there.
As she looks around, she suddenly sees a shaman man standing close to her. He pokes her forehead and chants. Freaked out, she moves down the steps and escapes the forest. Inside the temple, the mummified body begins to crack and a scream is heard.
Back at home, Winston senses something and begins to growl. Michael goes to the door, thinking it is Maria, but no one is there. Lucy stands behind him, saying the dog woke her up. Michael puts her back to bed.
The next day, Maria travels back home on the train. She looks at photos of Oliver on her phone.
Back at the house, Lucy is having a tea party in her room with her stuff animals. Suddenly she hears footsteps, so she goes to investigate. Looking up the stairs, where Oliver's room was, she finds Khan, Oliver's tiger, muddy from his grave. Though curious where it came from, she picks it up and is about to head back to her room, when she hears a noise at Oliver's room. The door creaks open slightly.
Maria arrives home finally. Piki sees her and nods. Michael comes in and asks what she was doing. I was trying to get better, Maria says, kissing him. She tells him that shes back for him and for Lucy.
That night, Maria and Michael hold each and kiss. Maria gets on top of him and takes her shirt off. They make love for first time in what must have been a long time. Later, as they sleep, Winston barks, waking her up. She pulls him out of the room, and then checks on Lucy. Maria walks back out into the hallway and sees Winston went down to the first floor and is whimpering at something, though she cannot see anything.
The next day, Maria checks on Lucy but doesn't find her in her room. Hearing noises, she checks Olivers room to find her playing in there. Maria tells her she doesn't want her playing in there and shoos her out. Maria packs up some toys in a small chest then goes to leave. When her back is turned, the toy chest topples over on its own. Maria looks at a set of blocks that have spelled out Oliver's name which shocks her.
Later, Maria hears Lucy on the piano, playing the song that she and Oliver used to play. As Maria tells her to stop, Lucy starts again, saying she wants to show her something. Maria pulls her hands away, only to see the piano continue to play by itself. Oliver's come back, Lucy says.
Maria washes Khan, making it look brand new. Staring at it, she breaks down in tears.
Later that night, Maria tucks Lucy into bed. Lucy thinks they should keep Oliver a secret. "I think Oliver is hiding", Lucy says. When Maria asks where, Lucy says Oliver won't tell her. Lucy says they probably shouldn't tell Michael and Maria agrees, saying it will be their secret until the time is right.
Maria goes up to Oliver's room and looks around. A book falls out a bookcase. It is the Jungle Book, a book she was reading to Oliver but did not finish before his death. A chair scraps towards the bed and a light turns on. Maria realizes Oliver wants her to read to him. Maria sits down and continues the story.
The next morning, Michael is in his office, pulling out some new pieces. Maria comes up to him and hugs him. She thinks she is feeling better. Unbeknownst to either of them, leaves that are falling in their yard immediately shrivel up and die when they hit the ground.
That night, Maria wakes up to see Khan staring at her. She looks around and hears Oliver's voice. Looking back at the bed, a grotesque figure is on the bed, screaming. Maria wakes up; it was another bad dream.
The next morning, Piki is in the kitchen working, when she notices a nearby plant is dead. A groundskeeper finds her and pulls her outside, showing her all the plants have died. Also, fish in a nearby pond are dead too. Piki begins to suspect something is horribly wrong and has to do with Maria and the ritual. Lucy screams and when they go to investigate, they find that the family birds have died too. Lucy asks if they can bury them at sea and Maria says "yes". Piki looks at Maria; she has her suspicions but isn't ready to confront her.
Maria and Lucy go to the ocean and bury the birds at sea. Lucy asks about a strange man and Maria sees a shaman chanting on rocks in the distance. Maria says he is far away, but Lucy says not that man. Maria turns around to find a second man chanting in her face. He rubs ash on her forehead, and Maria and Lucy leave quickly.
Maria and Lucy take a taxi through the city. Suddenly, traffic halts due to an accident. Maria goes to investigate and sees a dead man on the road. The mans head twists around to look at her, so Maria flees on foot with her daughter.
That night, rain falls. Lucy is watching TV. She calls out to Oliver, getting no response. As thunder strikes we see a small figure, standing nearby, watching her. It gets closer and closer until we see it is the decomposed body of Oliver.
Later, Lucy is taking a bath in the tub. Maria comes to wash her hair, when she notices a bite mark on her shoulder. Maria asks her what happened. "I don't think I like Oliver anymore. He's mean", Lucy says.
Later, goes up to Oliver's room and tells him he cant hurt his sister. Oliver replies by dropping the Jungle Book and bringing out the chair. Maria nods and says she will read to him but he can never hurt his sister again. He seems to accept the terms so Maria picks up where she left off.
Later, Maria gets a phone call from Michael saying he will be late and not to wait up for her. As she hangs up, Maria hears a door creak. Going to check, she begins to hear the piano play, even though she finds no one down there. Looking into the hallway, she finds Khan torn to bits. Someone knocks at the door. Opening it, she finds one of the shamans chanting outside. She tells him to leave before she calls the police. He points to her left. She turns to look and the grotesque figure from the temple is standing next to her. It chases her as she crawls on the ground as its body contorts and bones crack. Then, as quickly as they arrive, both figures disappear.
The next day, Piki finally confronts Maria. She knows Maria opened the temple door despite her explicit warning not to. She chides her for thinking she could bring Oliver back, that she could disrupt the balance between the dead and living. Piki tells her that due to her actions, Oliver's soul has been corrupted and turned evil. The strange figure she has been seeing is The Gate Keeper, who reclaims the soul of the dead, and will kill everyone in its way. Piki urges Maria to burn all of Oliver's possessions to break his hold on the living world or he will continue to cause harm to the family.
Maria checks on Lucy in her room, to find crying on her bed with her back turned to Maria. As she goes to touch her, Lucy comes out of the corner, asking her mother what is wrong. The figure on the bed twists its head around and screams at Maria, frightening her.
Later that day, Maria, trying to find a way out of her predicament, proposes to Michael they go back to the United States before Lucy starts school. Michael is open to the idea. Maria begins to hallucinate, thinking everyone is staring at her and cockroaches are coming out of the walls and are crawling through all the food. When Michael snaps her out of her trance, they both realize Lucy is missing. Maria goes out the back and goes to look for her in the busy streets, getting lost. Going down a dead end, she sees The Gate Keeper once more, who proceeds to lunge at her, shocking her. Michael shows up with Lucy right after, saying she was just outside the front door but she ran off before he could tell her.
Back at the house, Piki is gathering up all of Oliver's possessions in trash bags, getting ready to burn them. The door creaks. Piki pauses. "I know you're there", she states, before collecting more stuff. She takes it all out into the courtyard before returning to inside to get lighter fluid. She hears more noises and realizes she has been locked in. She pleads for Oliver to stop and to her surprise, the door unlocks. She goes outside and coats Olivers stuff in lighter fluid then struggles to light a match. Nearby, in the pond, the body of a young girl rises out of the water. It is Piki's daughter. The girl calls out to Piki, and Piki, though knowing something is wrong, is swayed into going closer out of motherly love. We see it is actually Oliver, mimicking the voice of Piki's daughter. Piki looks into the water and sees a hair bow. As she reaches down to it, we see Oliver's face in the water reflection.
Michael, Maria, and Lucy return to the house and find the pile of Oliver's things. Maria looks at the pond then screams for Michael to come over as she takes Lucy away. Michael looks into the pond and sees Piki's horrified face underwater. She was drowned by Oliver's spirit.
We see Michael at Pikis funeral as her body is burned in a pyre. Michael notices the shamans for the first time.
Maria gets Lucy ready for bed. Lucy asks if Oliver caused Piki's death. Maria tells her "no, it was just a terrible accident. Is Piki in heaven now?" Lucy asks. "I think so... yes", Maria replies. "Why isn't Oliver in heaven?" Lucy asks. Maria dodges answering the question and tells her goodnight.
Maria goes outside. Knowing she is responsible for everything, including Piki's death, she finds her courage, and burns the pile of Oliver's things.
In traffic, Michael has a hallucination of a monster outside his car. But it is just a beggar asking for change.
At home, Winston is barking a lot. Maria checks on Lucy to find her not in bed. She checks Olivers room but nobody is there either. Looking outside the window, she sees Lucy on the swing. She goes up to Lucy and asks why she is out of bed. "I wanted to feel the wind on my skin. It tickles", Lucy says.
Michael comes home and sees the bonfire, and promptly freaks out at losing all traces of his son. Maria tells him it has to burn, and tries to explain how it is all her fault. Michael thinks she is crazy, so Maria tries to talk to Lucy, and tell her to tell her father what has been happening. However, Lucy denies knowing anything about Oliver coming back, making Maria look crazy to Michael. Michael takes Lucy back inside, with Maria following. Maria sees Lucy has black eyes, and realizes the horrific truth; Oliver has possessed his own sister. However, Michael doesn't see any changes, and tells Maria is sick and he will get her help. He takes Lucy with him, and locks Maria in the room. As they head downstairs, the lights go out.
Michael sees the shamans outside so he tells Lucy to wait in the kitchen while he calls the police. While he is distracted, Winston growls at Lucy. Lucy hisses at him, telling him to be quiet. She notices a large butcher knife and picks it up.
As Michael gets off the phone, he hears the dog whimper and a splash of blood. Going back into the kitchen, he sees the dog dead with Lucy holding the kitchen knife. He asks Lucy what she did. Lucy/Oliver says the dog misbehaved and they hope he wont do the same. Lucy then proceeds to stab Michael in the chest. As he crawls away bleeding, he realizes that Maria was right. He asks Lucy why she did that. "I'm not Lucy, I'm Oliver!" Lucy states. Oliver plans to kill Michael so it will just be him (as Lucy) and his mother forever.
Maria breaks out of the room. She hears doors open, and goes down the hallway, a shaman standing behind her. She goes up to Oliver's room where a group of shamans are chanting over Lucy's body. Since they cannot extract the spirit, the only way to stop Oliver is to sacrifice Lucy.
On all fours, The Gate Keeper crawls up the stairs to Oliver's room.
Just as one of the men goes to strike, Michael stops him. Maria goes down to Lucy and tells Oliver that he needs to leave. Oliver says he is scared, but Maria says she will go with him (to save Lucy and atone for leaving him). Oliver's spirit leaves Lucy's body and hugs Maria, absorbing into her. She charges the shaman with the knife, telling him to take her instead. He obliges her, fatally stabbing her. She falls to the ground, with Michael and Lucy screaming in horror.
Maria awakens in the room alone. The Gate Keeper shows up soon after and pulls away her hands from her face. Maria looks deep into her eyes. The Gate Keepers eyes crack down the middle with light much like a door, and the light envelops Maria.
Back in the real world, Maria closes her eyes and dies. Lucy cries out for her mother, begging her not to go.
In the final scene, Maria wakes up and for a moment, believes she is alive. She hears Michael's voice calling out to her, and she responds. Michael says he can't believe it, that he has missed her so much. Maria gets up and sees the temple steps. She realizes to her horror that Michael is attempting the same ritual to say goodbye as she did with Oliver. Michael says he needs to see her one last time and begins to open the door. Maria screams at him not to open the door but the door is opened just as the screen goes black.
(Note: Since Michael disobeyed the rules too and opened the temple door, Maria's soul will be corrupted and turn evil. Maria will turn on her family, starting the curse anew.)