Watch Supernatural: Season 6, Episode 18

"Frontierland"

Sam, Dean and Bobby are doing research in the Campbell's library when Bobby finds a book that can help find a way to win against Eve, Bobby finds out that ashes from a phoenix can kill her although they thought they didn't exist. Dean finds Samuel Colt's diary, where it is mentioned that he killed a phoenix in Sunrise Wyoming in the year 1861. They decide to call Castiel so he can send them back in time, but instead one of Castiel's lieutenants called Rachel appears. She starts telling the brothers to stop calling Cass because he is busy, when Cass suddenly appears. After explaining the risks of sending someone so far away in time, he tells Sam and Dean they only have 24 hours in there, because he may not be able to bring them back if they stay longer than that and then proceeds to send them them back to time and place mentioned in the diary. As the brothers enter the town, Elias Finch is about to be hanged for for the murder of his wife. Finch informs the judge, the sheriff, and the deputy that they are all going to burn, then is hanged by the neck. Sam and Dean go to the sheriff to see if he knows anything about Samuel Colt, but he tells them to go talk to the local bar. There they find out that Samuel Colt is building some railroads 20 miles away from town, and then the judge goes to a bedroom with a prostitute, when Finch appears and burns him until he is just a pile of smoldering ash. Finch does the same to the sheriff, and Dean is proclaimed as the new town sheriff while Sam tries to find Samuel Colt. Sam finds him and presents himself a hunter from the year 2011 and gives his cellphone as proof, while he tries to convince Colt to help him kill Elias who is in fact the phoenix. Meanwhile, Rachel confronts Cass about his plan to win the war, after which she tries to kill him after telling him how could he be planning on doing that. Cass is seriously injured but manages to kill Rachel, after which he goes to Bobby's house. He tells Bobby he won't be able to bring the brothers back unless he can regain his power by touching a human soul, when Bobby offers himself to do it. Meanwhile back in 1861, Dean uses the deputy as a bait to Finch, who can't go through the iron bars where he the deputy is behind. Finch takes a gun and kills him, and starts to chase Dean. After losing sight of Finch, Dean finds Sam who was given the Colt gun. Dean kills Finch with the Colt, but are brought back by Cass right when they were going to get the ashes. After thinking everything is lost, a mysterious package from Samuel Colt comes that was supposed to be delivered that day to Bobby's house. Inside it was a letter to Sam telling him he got the address out of the cellphone. Along with the card, Sam took out his cellphone and a jar with the ashes of the phoenix.