'Supernatural' clip: Sam gives up hope, but Dean is determined to save him

spn-bai-dean.jpg "Supernatural" fans have been anticipating this week's episode, "The Born-Again Identity," all season. Not only are Castiel and Meg returning after long absences, but the breakdown that we've been expecting from Sam since midway through Season 6 has finally come to pass.

In this sneak-peek clip from Friday's episode, we get our first look at Sam after a complete mental meltdown. As we know from last week, he hasn't been sleeping -- and he doesn't take to the deprivation as well as he did when he didn't have a soul.

One thing we can count on from "Supernatural" is that Sam and Dean will always do their best to save each other from whatever dire fate awaits them -- and this is no exception. "Sam, I'm going to find you help," Dean tells Sam, hopefully, when he visits him in the asylum. Sam isn't quite so convinced this time, though. With Lucifer cracking jokes in his mind, Sam is about as close as we've seen him to complete surrender, and it's beyond unnerving to Dean.

"Dean, we knew this was coming. When we put my soul back, Cas warned us," Sam says. He's resigned himself to the fact that without sleep, he's likely to die. The longest a human has ever been awake, on record, is eleven days, and though there's no record of anyone actually dying from sleep deprivation, there's also no record of anyone being chased around by Lucifer for days on end. Animal testing has proven that brain damage and organ failure can result from lack of sleep.

Notably, when Sam brings up Castiel -- who broke Sam's brain in the first place -- Dean has a pretty strong reaction. "Screw Cas," he shouts. When we were on set, Jensen Ackles told us that when Dean actually sees Castiel later in the episode, he'll have a very different reaction, so it'll be interesting to see his desperation increase as Sam's condition worsens.

Photo/Video credit: The CW