Aside from season two, the past three season finales of Supernatural have ended with a cliffhanger. The season four finale started with the usual quick season recap set to Kansas' "Carry on My Wayward Son" that ended with the Sam walking out on Dean.

In the teaser set in a Maryland covenant in 1972, a demon-possessed priest explained to a group of nuns that his father was trapped and the door was there at the convent. The demon's eyes turned yellow, and revealed it was Azazel, the same demon that started that the Winchesters hunted before finally killing him in the season two finale. He also reminded them his father was an angel at a point and then advised him to pray, all before the screaming began.

Ruby tried to tell Sam that he and Dean would work things out but he didn't share her opinion. Sam recognized he had something evil inside of him and thought Dean was better without him. At Bobby's, Dean refused to call Sam while Bobby told him to keep trying to help Sam. Dean admitted he wasn't sure if Sam was his brother anymore or if he ever was and Bobby yelled about how immature Dean was being. Bobby told Dean to not be like John.

Dean turned around and was in a completely different room when the angels Zachariah and Castiel showed up. Zachariah explained that this was just a place for them to keep Dean safe and then Dean refused all of the perks offered to him. Zachariah reminded him he had sworn his allegiance to the angels.

Sam and Ruby found the demon nurse that was responsible for taking the babies to Lilith and tried to torture her for the information they needed. She didn't know anything, so she hid in the possessed woman's subconscious and left Sam with her host, who had no idea what happened to her.

Dean called Sam and managed to admit he's was still mad but remind Sam they were still brothers, with the long voicemail cutting out just before he could say he was sorry.
Back in 1972, Azazel used a dead nun's body to communicate with Lucifer. Lucifer told Azazel to find special children, proving the devil was directly responsible for organizing what had happened the last four seasons.

Sam and Ruby got on the road with the screaming woman in the trunk. Dean asked to see his brother but Castiel wouldn't take him to Sam. Dean tried to get out of the room by breaking a hole in the wall and Zachariah returned. Zachariah admitted that Dean wasn't going to stop the apocalypse and the angels were okay with that, because it would lead to peace on Earth. Zachariah also acknowledged innocent humans would die in the process. The angels weren't entirely playing with Dean, because it turns out that he does have a huge part in what's to come. He has to kill Lucifer. As for what happens to Sam, Zachariah told Dean that Sam had a part to play.

Castiel tried to get Dean to understand the angels' side but Dean only cared about what would happen to the rest of the world. Castiel said he couldn't let Dean out of the room because they would be hunted and killed. Dean told Castiel they were done.

Ruby tried to hurry Sam along and convince him to take the nurse's demon blood, but he took a minute to check his voicemail. Sam heard Dean calling him a monster and hung up. The nurse kept screaming as Ruby opened the trunk, with Sam unable to watch.

Dean was moping when Castiel returned and cut and smeared his own blood in a symbol to get them out of the room. Castiel explained that Lilith dying was the final seal. The prophet, Chuck was trying to order twenty prostitutes when Dean and Castiel showed up. Castiel sent Dean to stop Sam and stayed to make sure the Chuck's archangel protection didn't follow.

Sam finally made it to Lilith and started to kill her when he heard Dean yelling his name. Sam stopped, but Lilith taunted him until his eyes turned black and he finished the job. With Lilith dead, Ruby finally congratulated Sam on starting the apocalypse. Ruby explained that only Lilith knew what Ruby was really up to and Sam tried to kill her. Ruby told Sam that Lucifer would reward him in ways that he couldn't imagine.

Dean finally broke through the door and Sam held Ruby while Dean killed her. Sam apologized and the boys watched as the floor began to open. Will Sam be the host for Lucifer? Will Dean be able to stop Lucifer? What's going to happen to Castiel? All of these questions will have to wait for the premiere of season five.

Supernatual Cast: Jared Padalecki, Jensen Ackles, Jeffrey Dean Morgan, Nicki Lynn Aycox, Jim Beaver, Katie Cassidy, more

Story by Lauren Attaway

Starpulse contributing writer

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