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 100th-episode party, someone said, "Maybe we'll see you at the 200th!" and everyone laughed at the idea, thinking the show would be long gone by that time. The party for the 200th episode of the series took place in October 2014.
Riverview Hospital, a large mental health facility used as the main set in the Season 1 episode "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.
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 10.
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 recasting 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.
With the CW's announcement that the series was renewed for a 12th season, It breaks the current record for the second longest running consecutive science0fiction series, second to the BBC's Doctor Who (1963). Smallville (2001) (which also featured Jensen Ackles) held the record previously.
Misha Collins (Castiel) was originally only supposed to make a couple of guest appearances in Season 4, but due to enormous fan response he has been a regular on the show ever since. 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.
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 38 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.
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.
In Season 2, Linda Blair guest-stars as a detective investigating the brothers. At the end of the episode she says, "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".
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 1, Episode 4, Supernatural: Phantom Traveler (2005), 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.
Jared Padalecki and Jensen Ackles auditioned for the role of Superman/Clark Kent in some form. Padalecki was a finalist for director McG's reboot, while Ackles was the second choice to play a young Clark Kent in the show Smallville (2001). He was later cast as Jason Teague in Season 4.
The "Supernatural" fan base is repeatedly referenced throughout the show, and even makes a few special appearances, including the 200th episode. This was made possible through the character Chuck Shurley and his prophetic book series about the Winchesters.
Dean's car, up until Season Two, Episode 20, 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. The plates are changed again in later seasons to Oregon plates SMD 5B2, as seen in Season 7, Episode 13.
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."
In Season 2, Episode 12, Supernatural: Nightshifter (2007), the magazine that Ron shows Sam and Dean (disguised as FBI agents) has a picture of a humanoid metal robot, or "Mandroid" as Ron insists on calling it, with the caption "Cyberman". Both the name "cyberman" and the likeness of the robot are references to Doctor Who (1963), with the cybermen being prominent antagonists in the show.
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 1, Episode 9 do they refer to themselves as Dean and Sam.
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 2, Episode 18, Supernatural: Hollywood Babylon (2007), 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.
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.
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.
In Season 12, 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 a Season 2 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 (1997).
This is the second time Jensen Ackles has played a sibling to a character named Sami/Sammy, as he previously appeared on the daytime soap opera 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.
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.
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.
In Season 2, Episode 18, the posters on the writers' office wall depict a Monster Horror Truck and Carnival, both of which were story lines in Season 1. Also, the director of the horror film in this episode's story line is none other than the executive producer of the show, McG.
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.
In Season 2, Episode 4, 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.
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 [traffic] lights, they lock their doors.'
Angels were introduced in Season 4, when Castiel appeared for the first time. Dean didn't believe in angels, unlike Sam. With Castiel and the other angels, "Supernatural" soon turned into Apocalypse, changing the whole concept to match Christian ideology.
In Season 2, Episode 18, when Sam and Dean go to Hollywood and are taking the tour, the tour guide mentions the show Gilmore Girls (2000) being shot just as Sam says they need to get off. Jared Padalecki had a prominent role on that show before being cast in "Supernatural".
Although it has never been confirmed when the last season of Supernatural will be, it was hinted that it could be their 14th or 15th season. However, the two stars of the show, Jared Padalecki and Jensen Ackles, said recently that they would like to exceed past the 300 episode mark (15 seasons).
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.
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.
Genevieve Cortese was cast as Ruby for Season 4 (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 makes jokes about Hanukkah and keeping kosher and, most significantly, when he dies the Winchester brothers and Bobby give him a funeral in a Jewish cemetery, and discuss 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).
Jared Padalecki has played the greatest number of characters for an individual actor on the show. He not only plays Sam Winchester but has also 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 makes his first appearance in Season 3, Episode 10.
Dean's primary sidearm is a Colt Series 70 1911, with a nickel finish, full engraving and ivory grips, chambered in .45acp. Sam carries a Taurus PT92 with a stainless-steel finish, mother-of-pearl grips and chambered in 9mm. The only exception is in Season 6, 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 Supernatural: The Girl Next Door (2011), 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 Supernatural: Swan Song (2010) 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.
In the Season 11 episode Supernatural: The Devil in the Details (2016), 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.
The biblical Burning Bush Sam sees at the beginning of Season 11, Episode 9, Supernatural: O Brother, Where Art Thou? (2015), is a popular ornamental shrub in the Euonymus genus, Euonymus alatus, commonly known because of its fiery autumn foliage as "Burning Bush".
In Season 4, Episode 17, Supernatural: It's a Terrible Life (2009), Dean and Sam are both 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.
In the Season 12 finale Crowley kills himself to close a portal to an alternate world and Lucifer stabs Castiel, killing him. While it is unclear if Misha Collins will be returning as a regular for Season 13, Mark Sheppard has stated that he will not be returning.
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 story line, 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 story line of angels and demons, and their fight for Earth in the end times, and to show how things can be divided.
In Season 4 it was said that Dean's necklace amulet burned bright and hot when God is near. When the brothers met Carver Edlund (Chuck) in that same season, it never burned. In Season 11, Episode 20, Supernatural: Don't Call Me Shurley (2016), however, Dean's amulet "appears" in Sam's pocket, and glows when near Chuck. Later, however, Chuck reveals to Metatron that he can turn the amulet "on and off" as he pleases.
Cain's house in Season 9 Episode 11, Supernatural: First Born (2014), in which Dean and Crowley go to find the first blade which ends up being Cain's house, is the exact same house that was used in Season 3 Episode 1, Supernatural: The Magnificent Seven (2007), at the beginning when Sam and Dean are "outside Lincoln, Nebraska" where Bobby has just sent them to investigate.
In Season 11, Episode 10, Supernatural: The Devil in the Details (2016), when Sam is talking to Lucifer in the cage at 30:35, Lucifer makes a remark about what he would do if he were topside again. Sam asks, "Even if you did gank her, then what?" To which Lucifer quickly responded, "Move to L. A., solve crimes". This was very likely a reference to Fox's new show at the time, Lucifer (2015), which had that exact same plot line and which, coincidentally enough (?), premiered five days after this episode aired.
Jensen Ackles was asked who he imagined was dying in his arms while filming Sams death scene in season 2 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.