01. Sympathy For The Devil:
Picking up where the finale left off, Dean (Jensen Ackles) and Sam (Jared Padalecki) watch as the Devil (guest star Mark Pellegrino, "Lost") emerges from Hell.
The brothers and Bobby (Jim Beaver) deal with the aftermath of Lucifer rising and the stunning news from Chuck the Prophet (guest star Rob Benedict) that Castiel (Misha Collins) was blown to bits by the archangels.
02. Good God Y'all:
Castiel (Misha Collins) tells Sam (Jared Padalecki) and Dean (Jensen Ackles) that he is going to search for God, who will be able to defeat Lucifer.
Bobby's (Jim Beaver) old hunter friend, Rufus (guest star Steven Williams), is panicked about demons attacking his town, and begs Bobby for help.
Sam and Dean arrive at the town and realize there is a spell over the townspeople, making them hallucinate that they are demons and causing them to kill one another.
03. Free To Be You And Me:
Not sure he trusts himself anymore, Sam (Jared Padalecki) decides to give up hunting, but a late-night visitor (guest star Adrianne Palicki) won't let him off the hook that easily.
Dean (Jensen Ackles), intent on stopping the Apocalypse, continues hunting on his own and teams up with Castiel (Misha Collins) to find the Archangel Raphael, as Castiel believes Raphael knows God's location.
04. The End:
Sam (Jared Padalecki) tells Dean (Jensen Ackles) he wants to rejoin Dean in the battle of the Apocalypse, but Dean tells Sam that they are better off apart. Later, Dean awakens five years in the future in an abandoned city and is attacked by humans who have been infected with a demonic virus that turns humans into Zombies.
Zachariah (guest star Kurt Fuller) appears to Dean and explains that this is the world that exists as a result of Dean saying no to helping the angels fight Lucifer.
Dean meets up with Future Dean, who tells him that the virus is the Devil's endgame for destroying mankind.
05. Fallen Idol:
Sam (Jared Padalecki) and Dean (Jensen Ackles) decide to start hunting together again and their first case leads them to a small town whose inhabitants are being killed by famous dead icons like Abraham Lincoln and James Dean's car.
However, after two teenage girls come forward and claim their friend was kidnapped by Paris Hilton (in a cameo role as herself), the brothers aren't sure what they are hunting anymore.
06. I Believe The Children Are Our Future:
Sam (Jared Padalecki) and Dean (Jensen Ackles) investigate a series of odd murders that strangely resemble fairytales and urban legends.
The brothers track down an 11-year-old boy named Jesse (guest star Gattlin Griffith) and realize that whatever Jesse believes is coming true.
Castiel (Misha Collins) tells Sam and Dean that Jesse is a serious threat and needs to be eliminated.
07. The Curious Case Of Dean Winchester:
Sam (Jared Padalecki) and Dean (Jensen Ackles) discover a witch (guest star Hal Ozsan) is running a high-stakes poker game where the currency is life years vs. money. Bobby (Jim Beaver) sees the game as a chance to get out of the wheelchair and bets 25 years, but loses.
As Bobby begins to age rapidly, Dean steps in to save him but also ends up turning into an old man, leaving Sam holding the bag for their survival.
08. Changing Channels:
The Trickster (guest star Richard Speight Jr.) throws Sam (Jared Padalecki) and Dean (Jensen Ackles) into an alternate universe where they are characters in different television series, including a sexy medical show, a Japanese game show, a forensics show and a sitcom.
The brothers realize the only way to get out of this world is to play along and become the characters in the shows. However, Castiel (Misha Collins) appears and warns them this universe is dangerous and they must get out before they become trapped.
09. The Real Ghostbusters:
Super fan Becky (guest star Emily Perkins) uses Chuck's (guest star Chuck Benedict) phone to trick Sam (Jared Padalecki) and Dean (Jensen Ackles) into attending a Supernatural fan convention, complete with fans dressed up as Sam and Dean.
One of the activities is a live action role playing game, but things quickly turn sour after a real ghost appears on the scene.
10. Abandon All Hope:
Sam (Jared Padalecki), Dean (Jensen Ackles) and Castiel (Misha Collins) track down the Colt and head off to find Lucifer (guest star Mark Pelligreno) to send him back to Hell. It's a hunters' reunion when the crew joins forces with Bobby (Jim Beaver), Ellen (guest star Samantha Ferris) and Jo (guest star Alona Tal) for what could be their last night on Earth.
11. Sam, Interrupted:
A former hunter named Martin (guest star), who is currently institutionalized, calls Sam (Jared Padalecki) and Dean (Jensen Ackles) for help investigating a case in the mental hospital. The brothers get themselves admitted as patients to check out the mysterious monster that is attacking the patients, but their incarceration pushes both to the breaking point as they unleash their inner demons against each other.
12. Swap Meat:
Gary (guest star Colton James), a teenage nerd, conjures up a body-switching spell and changes bodies with Sam (Jared Padalecki). Thrilled by his new handsome and built body, Gary (now Sam) investigates a case with Dean (Jensen Ackles) and takes advantage of his good looks and age by hitting on women and getting drunk. Meanwhile, Sam is stuck in Gary's teenage body, dealing with intrusive parents and high school.
13. The Song Remains The Same:
The angels send Anna (guest star Julie McNiven) back in time to kill John (guest star Matthew Cohen) and Mary (guest star Amy Gumenick) Winchester before they can conceive Sam (Jared Padalecki) knowing that if Sam was never born then Lucifer won't be able to use him as his vessel. Castiel (Misha Collins) sends Sam and Dean (Jensen Ackles) back to 1978 so they can stop Anna, and the two brothers are reunited with their parents. Mary recognizes Dean as a hunter since he visited her in the past once before but tries to keep the truth from John.
14. My Bloody Valentine:
Castiel (Misha Collins) helps Sam (Jared Padalecki) and Dean (Jensen Ackles) hunt down Cupid (guest star Lex Medlin) on Valentine's Day after townspeople start to kill each other for love. However, after Cupid tells them he's innocent, they discover Famine (guest star James Otis), one of the Four Horsemen of the Apocalypse, has arrived in town.
15. Dead Men Don't Wear Plaid:
Sam (Jared Padalecki) and Dean (Jensen Ackles) investigate Bobby's home town where the dead are rising from the grave but instead of attacking humans, they are happily reuniting with their families.
The brothers turn to Bobby (Jim Beaver) for help but he tells them not to worry about it and to leave town. Suspicious, Dean investigates and comes face to face with Bobby's dead wife (guest star Carrie Anne Fleming) who has no memory of what happened to her.
Once the zombies start turning evil, the boys tell Bobby he has to kill his wife but he refuses.
16. Dark Side Of The Moon:
Ambushed by angry hunters, Sam (Jared Padalecki) and Dean (Jensen Ackles) are shot and killed and sent to Heaven.
Castiel (Misha Collins) warns Dean that Zachariah (guest star Kurt Fuller) is looking for them in Heaven so they need to lay low while searching for an angel named Joshua (guest star Roger Aaron Brown) who can help them since he talks directly to God.
While searching for Joshua, the brothers run into some old friends and family members.
17. 99 Problems:
Sam (Jared Padalecki) and Dean (Jensen Ackles) are outnumbered by demons, but are saved at the last minute by Rob (guest star Michael Shanks) and his townspeople, who are aware of the Apocalypse, and have been training to fight and kill demons.
The small town is very religious and Sam and Dean meet Pastor Gideon (guest star Larry Poindexter), who introduces them to his daughter Leah (guest star Kayla Mae Maloney), whom he claims is a prophet.
Leah tells the townspeople they must obey her orders if they want a spot in Heaven but when she starts turning the townspeople against each other in the name of the Lord, the brothers realize they must kill her.
18. Point Of No Return:
Dean (Jensen Ackles) begins to think the only way to stop Lucifer is to say yes to Michael, but the angels decide they don't need him anymore.
Dean, Sam (Jared Padalecki) and Castiel (Misha Collins) are horrified at the angels' new game plan and take on Zachariah (guest star Kurt Fuller) to prevent an all out war on Earth.
Meanwhile, a familiar face returns.
19. Hammer Of The Gods:
Sam (Jared Padalecki) and Dean (Jensen Ackles) are kidnapped by a group of gods, including Kali (guest star Rekha Sharma), Ganesh (guest star Keith Blackman Dallas) and Bladur (guest star Adam Croasdell) and held hostage in a small hotel.
The gods want to use Sam and Dean as bargaining chips to stop the Apocalypse, but Gabriel (guest star Richard Speight, Jr.) shows up and warns them that if Lucifer finds them he will kill them all.
Unfortunately, one of the gods turns on the rest and Lucifer appears.
20. The Devil You Know:
The demon Crowley (guest star Mark Sheppard) tells Sam (Jared Padalecki) and Dean (Jensen Ackles) he can help them find the remaining Horsemen rings so they can trap Lucifer.
The brothers are doubtful until Crowley leads them to Brady (guest star Eric Johnson), the Handler for Pestilence (guest star Matt Frewer) and Death.
However, Brady refuses to give up their locations and sets Pestilence after the Winchesters.
21. Two Minutes To Midnight:
Crowley (guest star Mark Sheppard) tells Bobby (Jim Beaver) he will give him the location of Death (guest star Julian Richings), the fourth horseman, in exchange for his soul. Knowing Sam (Jared Padalecki) and Dean (Jensen Ackles) need that fourth ring to stop the Apocalypse, Bobby reluctantly agrees.
Sam and Dean confront Pestilence (guest star Matt Frewer), but he unleashes a deadly virus upon them, so Castiel (Misha Collins) must intervene on their behalf.
Dean has a meeting with Death to discuss Lucifer, and an unholy alliance is formed at a very high price for Dean.
22. Swan Song:
The entire season has been leading up to this showdown between good and evil. With the Apocalypse looming, Sam (Jared Padalecki) and Dean (Jensen Ackles) realize they are out of options and make heart-breaking decisions that will change their lives forever. A beloved character is killed.