He ends up inside a mental hospital as the doctor’s try to help him, but I he goes too much longer without sleep, his body is going to shut down. Dean starts calling around to see if there is any shaman or faith healer that might be able help his brother, but comes up with nothing.
That is until suddenly a card falls from the book with a number. (Bobby…are you there.) The number is another hunter that was healed by a man named Emanuel. Dean tracks him down and …queue the drum roll..it’s Castiel with no memory. Crowley hear there’s a human healing people and dispatched some demons to take him. Dean saves him and has an awkward conversation because he doesn’t want to let on this guy is actually angel.
As they duo make their way to same, they get ambushed by demons and who steps in to save them…Meg. At the hospital demons are waiting outside and there are too many for them to handle. They finally tell Cas who he is and as he destroys the demons his memory comes back. He tries to help same, but he is too far gone. At the last minute, Castiel takes the evil into him and suddenly he is the one with visions of the devil and Sam is back to normal.
They brothers left with Castiel locked up in the loony bin apparently catatonic.