None of the cast or crew members ever expected the show to last as long as it has. Misha Collins (Castiel) has stated that at the one hundredth episode party, someone said, "Maybe we'll see you at the two hundredth!", and everyone laughed at the idea, thinking the show would be long gone by that time. The party for the two hundredth episode of the series took place in October 2014.
Jared Padalecki (Sam Winchester) dislocated his shoulder while wrestling with Osric Chau (Kevin Tran). The writers were then forced to make up a story as to why Sam was wearing a sling in the beginning of season ten.
Riverview Hospital, a large mental health facility used as the main set in season one, episode ten, "Asylum", has also substituted for a prison, a regular hospital, and an apartment building on different episodes of the series. This is evidenced by seeing the same distinctive staircase in different episodes.
An important aspect of the show's music is classic rock, most of which comes from Eric Kripke's own record collection, although one of his favorite bands, Led Zeppelin, has always been too expensive to license.
Originally, Jensen Ackles auditioned for the role of Sam Winchester. When Jared Padalecki came in and read for Sam, a slight re-casting was done. Producers called Jensen and asked if he'd rather use his charm for Dean, saying he was the Han Solo character of the duo, and what kid didn't grow up wanting to be Han Solo? Jensen accepted. It became known that he was previously interested in that role, because Dean was funny.
While it may be coincidental, the choice of the name "Winchester" for the family is interesting. There is a rather famous mansion in California built by Sarah Winchester, wife of the gun magnate, which was under constant construction for thirty-eight years for paranormal reasons. According to legend, the reason for the constant building, was that a medium told Mrs. Winchester that if she ever stopped building, the spirits of people killed by people using Winchester rifles, would come after her. The strange design of the mansion is also attributed to this. It was built with dead ends and stairs to nowhere, allegedly to confuse spirits.
With the CW's announcement that the series was renewed for a twelfth season, It breaks the current record for the second longest running consecutive science fiction series, second to the BBC's Doctor Who (1963). Smallville (2001) (which also featured Jensen Ackles) held the record previously.
In season two, Linda Blair guest-starred as a detective investigating the brothers. At the end of the episode, she said, "I need you two out there doing what you do best. I know I'll sleep better at night." This is clearly a nod to her role as Regan in The Exorcist (1973), as she was possessed by a demon. As the brothers walk away Dean says, "Does she look familiar to you?" Then he exclaims that he is craving pea soup, which was what Blair projectile-vomited in The Exorcist (1973).
The car Sam and Dean drive is a 1967 Chevrolet Impala four-door sedan, which used to be known as the Metallicar by fans of the show. The show uses five black Impalas. Dean has nicknamed the car "Baby", as it is also known by fans today.
Jared Padalecki and Jensen Ackles auditioned for the role of Superman (Clark Kent) in some form. Padalecki was a finalist for Director McG's movie, while Ackles was the second choice to play a young Clark Kent in Smallville (2001). He was later cast as Jason Teague in season four
Many of the episodes are based on existing legends, myths, and ghost stories. For example, the episode "Crossroads" is based in part on the legend of blues player Robert Johnson, who in turn, borrowed it from another blues singer.
In season one, episode four, "Phantom Traveller", Dean and Sam discover that every time someone says God's name in Latin (or Christo for Christ) out loud, demons will react most ferociously. They never used that same tactic again.
This show's fan base is repeatedly referenced throughout the show, and even makes a few special appearances, including the two hundredth episode. This was made possible through the character Chuck Shurley, and his prophetic book series about the Winchesters.
Show Creator Eric Kripke is a big fan of classic rock, and thus wanted it to be played on the show. He wrote in the pages of the pilot script "CUE MUSIC And you can take your anemic alternative pop and shove it up your ass. Dean plays bass thumping, pile driving (Led Zeppelin), and he plays it loud."
Dean's car, up until season two, episode twenty, "What Is and What Should Never Be", had Kansas (the brother's origin state) plates with the number KAZ 2Y5. It currently now has Ohio (Eric Kripke's home state) plates, with a Franklin County sticker (25) and the number CNK 80Q3.
In season two, episode eighteen, "Hollywood Babylon", while walking to Stage 9, Dean mentions wanting to take time off and go swimming, to which Sam responds "This seems like swimming pool weather to you, Dean? It's practically Canadian." This is a nod to the actual filming locations in the show, which are all in Canada.
Whenever a character is having a drink from a "to go" cup through a straw, especially Dean, you almost always hear a gurgling sound as if the cup is almost empty, even if it was just purchased, which is an all-too-common sound effect used on television shows and movies.
The character of Bobby Singer was originally supposed to be named Bobby Manners, after Robert Singer and Kim Manners, who had both greatly contributed to the show. However, after discovering that there was an actual Bobby Manners, the character's last name was changed to Singer.
In season one episode 3 "Dead in the water", Sam and Dean, posing as U.S. Wildlife Service agents, use the aliases "Agent Ford" and "Agent Hamill". This is a reference to Harrison Ford and Mark Hamill, from Star Wars: Episode IV - A New Hope (1977), of which Jensen Ackles (Dean) is a huge fan.
In season twelve, Dean (Jensen Ackles) can be seen playing the game Scrabble on his phone, with his mom (Mary Winchester) as his opponent. After he plays the word "twerking", the next set of letters for his next turn spells out the name "Lucifer".
In season two, episode twelve, "Nightshifter", the magazine that Ron shows Sam and Dean (disguised as F.B.I. Agents) has a picture of a humanoid metal robot, or "Mandroid" as Ron insists on calling it, with the caption "Cyberman". The name "cyberman", and the likeness of the robot, are references to Doctor Who (1963), with the cybermen being prominent antagonists in the show.
Dean's car, a 1967 Chevrolet Impala, is shown to have police-style spotlights on the front of car during the first three seasons. In later episodes, they are missing. The car wranglers state that this is because they had a hard time finding additional Impalas of that year with the police-style spotlights.
Whenever the brothers are introduced (by their real names) by themselves or others they are almost always referred to as Sam and Dean rather than Dean and Sam. This is a nod to Jared Padalecki's name being displayed first in the opening credits. Only in season one, episode nine, "Home", and season eight, episode fourteen, "trail and error" and again meeting Metatron in season eight, episode twentyone, "the great escapist" do they refer to themselves as Dean and Sam.
Misha Collins has created something on Tumblr called "Mishapocalypse" where on April 1, everyone in the "Supernatural" fandom does the following: Posts pictures of Misha, changes their profile picture to Misha's serial killer face, refers to each other as Misha and trick other fandoms.
A crossover with Smallville (2001) was proposed, but scrapped. Sam and Dean would have to save Tom Welling from the infamous "Superman curse" that has supposedly victimized several actors that have played Clark Kent/Superman.
In season four, episode eighteen, "The Monster at the End of This Book", when Sam and Dean meet the man who writes about them, they eat in a diner called Kripke Hollow, named after Producer Eric Kripke.
In a season two episode, Amber Benson plays "vegetarian" vampire Lenore, who refuses to feed on humans. She is best known for her character Tara, a witch who is friends with, and helps the title character, on Buffy the Vampire Slayer (1996).
Sam and Dean often use a Latin exorcism rite called the "Rituale Romanum". Translated to Enlgish it means: "We exorcise you, every impure spirit, every Satanic power, every incursion of the infernal adversary, every legion, every congregation and diabolical sect. Thus cursed demon, and diabolical legion, we adjure you. Cease to deceive human creatures and to give to them the poison of eternal Perdition. Go away, Satan, the inventor and master of all deceit, the enemy of humanity's salvation. Be humble under the powerful hand of God, tremble and flee! I invoke by us the sacred and terrible name at which those down below tremble. From the snares of the devil, free us, oh Lord. So that you may make your Church safe to serve you freely, we ask you, hear us. So that you may destroy the enemies of your sacred Church, we ask you, hear us."
This is the second time Jensen Ackles has played a sibling to a character named Sami/Sammy, as he previously appeared on Days of Our Lives (1965) as Eric, twin brother to Alison Sweeney's Samantha Brady. Sweeney's character usually went by the name Sami. Ackles' character tends to call his brother Sam, "Sammy" on this show.
Creator Eric Kripke's original choice for the Winchesters' car was a 1965 Mustang. He changed his mind after a neighbor said to him that it has to be a '67 Chevy Impala, "because you can put a body in the trunk. You want a car that, when people stop next to it at lights, they lock their doors."
Jared Padalecki's nickname is Jerry, and Jensen Ackles' is Jesse. Back in the 1990s, when he wasn't a star yet, Ackles was known only as Jesse Ackles, before he decided to use his full first name when his career started in Dark Angel (2000), starring Jessica Alba.
In season two, episode eighteen, "Hollywood Babylon", the posters on the writers' office wall depict a Monster Horror Truck and Carnival, both of which were storylines in season one. Also, the director of the horror film in this episode's storyline, is Executive Producer McG.
In season two, episode four, "Children Shouldn't Play with Dead Things", after a fight with a spirit, Sam states that he thinks he broke his hand. In the next few episodes, he is seen with a cast on his right arm. This is because Jared Padalecki broke his wrist during a stunt on the previous episode, so his injury was written into the script to explain the presence of his cast in the following episodes.
Although it has never been confirmed when the last season of this show will be, it was hinted that it could be their fourteenth or fifteenth season. However, Jared Padalecki and Jensen Ackles, said recently that they would like to exceed past the three hundred episode mark (fifteen seasons).
In season two, episode eighteen, "Hollywood Babylon", when Sam and Dean go to Hollywood, and are taking the tour, the tour guide mentions Gilmore Girls (2000) being shot just as Sam says they need to get off. Jared Padalecki played a prominent role on that show before being cast on this show.
Angels were introduced in season four, when Castiel appeared for the first time. Dean didn't believe in angels, unlike Sam. With Castiel and the other angels, this show soon turned into Apocalypse, changing the whole concept to match Christian ideology.
Resembles, by concept, The Forsaken (2001) starring Brendan Fehr and Kerr Smith as two vampire slayers who team up and drive across America in the same car, with a similar mission of the Winchester brothers, except being just best friends instead.
The trivia items below may give away important plot points.
Early on in the series, Dean's cell number is given, and for a while the studio had it set up so that anyone dialing the number would hear Jensen Ackles reading the message: "This is Dean Winchester. If this is an emergency, leave a message. If you are calling about 11-2-83, page me with your coordinates." The number is 1-866-907-3235. This number now leads to a fax machine, but it is not known where that fax machine ends up.11-2-83 is Sam and Dean's mother Mary Winchester's death date.
Misha Collins (Castiel) was originally only supposed to make a couple of guest appearances in season four, but due to enormous fan response, he has been a regular on the show ever since. Kripke has cancelled the death of Castiel twice, due to fans. Collins has joked that he maybe wouldn't have used such a low gravelly voice for his role, had he known he'd be on the show so frequently, because it hurts his throat.
Producers considered several methods of motivating Sam to take to the road with Dean. Turning Jessica evil was an option briefly, but in taking a page from Star Wars: Episode IV - A New Hope (1977), it was decided that her death would be the ultimate motivation for leaving home.
Sam was sick for a large part of season eight, due to the Demon Trials, and Jared Padalecki's performance was so convincing, that some fans became concerned about him, worrying that he was actually sick.
Genevieve Cortese was cast as Ruby for season four (replacing Katie Cassidy), and her character eventually becomes romantically involved with Sam (Jared Padalecki). In their real-lives, Cortese and Padalecki also became romantically involved, and after they married in 2010, she changed her last name to "Padalecki", both personally and professionally.
Several references, throughout his appearances on the series, point toward the character Rufus Turner (played by Steven Williams) being Jewish. He made jokes about Hanukkah and keeping kosher, and, most significantly, when he died, the Winchester brothers and Bobby give him a funeral in a Jewish cemetery, and discussed his level of Jewish ritual observance (or lack thereof). Although the funerals for previous hunters had included a ceremonial funeral pyre, the show makes a point of showing that Rufus gets buried without cremation (since cremation is against Jewish tradition).
Misha Collins has played the greatest number of characters for an individual actor on the show. He not only plays Castiel but has also played Lucifer, Jimmy Novak, Leviathan!Cas, Human!Cas, EndVerse!Cas, Crazy!Cas, God!Cas, and even himself, Misha Collins. Jared Padalecki plays as many characters. Besides Sam, he played Lucifer, Gadreel, Leviathan Sam, Souless Sam, Shapeshifter Sam, Himself, and briefly Meg. Oddly enough, Jensen Ackles, his on-screen brother, has played the fewest characters, playing only Dean Winchester, Leviathan Dean, Shapeshifter Dean, and Himself. In a later season, he also played Demon Dean, when the mark of Cain changed him. Demon Dean made his first appearance in season three, episode ten, "Dream a Little Dream of Me".
Dean's primary sidearm is a Colt Series 70 1911, with a nickel finish, full engraving, and ivory grips, chambered in .45 caliber. Sam carries a Taurus PT92 with a stainless-steel finish, mother-of-pearl grips, and chambered in 9mm. The only exception is in season six, when Sam loses his soul. "Soulless Sam" carries an HK USP Expert, chambered in 9mm. Once Sam regains his soul, he switches back to the Taurus PT92.
In season eleven, episode ten, "The Devil in the Details", while Sam is in the cage with Lucifer, he asks what he (Lucifer) will do after killing Amara. Lucifer responds with, "move to L.A., solve crimes." This is a nod to the FOX show Lucifer (2015), where Lucifer lives in Los Angeles and works with L.A.P.D. detective Chloe Decker to solve crimes.
In season five, episode five, "Fallen Idols", Paris Hilton was a guest star. At the end of that episode, Dean says: "I've never even seen House of Wax." House of Wax (2005) starred Hilton and Jared Padalecki.
In the season twelve finale Crowley kills himself to close a portal to an alternate world and Lucifer stabs Castiel, killing him. While Misha Collins does later return, Mark Sheppard has stated that he will not be returning.
In season seven, episode three, "The Girl Next Door", there's a scene where a leviathan is checking over a credit card statement, and asks about "Mistress Magda" before hanging up on the customer, because of getting a trace on Dean and Sam. Mistress Magda is the name Chuck says when he answers the phone in season five, episode twenty-two, "Swan Song", when Dean calls for the location of the fight between Michael and the Devil, the thought to be the last time we see Chuck, and he mysteriously disappears in a puff of white smoke.
Jensen Ackles was asked who he imagined was dying in his arms while filming Sam's death scene in season two, to create his believable reaction. Jensen answered that all he had to do was imagine that Jared was actually dying, because by then he already saw Jared as a brother.
In season four, episode seventeen, "It's a Terrible Life", Dean and Sam are put into an alternative life by an angel, they don't know who each other are, and they are called Dean Smith and Sam Wesson, a reference to the famous weapons company Smith & Wesson.
The Biblical Burning Bush Sam sees at the beginning of season eleven, episode nine, "O Brother Where Art Thou?", is a popular ornamental shrub in the Euonymus genus, Euonymus alatus, commonly known because of its fiery autumn foliage as "Burning Bush".
There's a Herpexia ad in the top right corner of the lab in the beginning of season five, episode twenty, "The Devil You Know", in reference to Sam's herpes commercial in season five, episode eight, "Changing Channels".
John and Mary are a reference to Jesus' parents from the New Testament. John Winchester baptizes Dean and Sam into the life of hunting monsters, and Mary gives birth to the two men who will decide the fate of the world. As can be seen in the progression of the series, many of the demons, ghosts and enemies of Sam and Dean are based on legends and stories from different cultures. The series in particular has a Biblical storyline, and as depicted by the names of the Winchesters' parents, the brothers were born to live and fight during the Apocalypse, as the saviors of the world and mankind. Although the series itself was not specifically designed to offend anyone, there is an underlying storyline of angels and demons, and their fight for Earth in the end times, and to show how things can be divided.
Cain's house in season nine, episode eleven, "First Born", in which Dean and Crowley go to find the first blade, which ends up being Cain's house, is the same house that was used in the season three opener, "The Magnificent Seven", at the beginning, when Sam and Dean are "outside Lincoln, Nebraska", where Bobby has just sent them to investigate.
In Season 6, when tracking the demons hunting alphas, the demon coordinating the others is named Ellsworth. Ellsworth is said to be Bobby Singer's counterpart. Bobby, played by Jim Beaver, also played a character named Ellsworth on the show Deadwood