Supernatural's Sam Winchester isn't about to stop trying to save his brother, a decision that will lead Dean to do something drastic.

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The younger Winchester brother is hell bent on removing Dean's (Jensen Ackles) rage-inducing Mark of Cain, and his efforts will put his own life on the line. As per usual, Dean will also pull out all the stops to make sure little Sammy (Jared Padalecki) survives as well, and the boys' competing desires will set them up for intense consequences.

"It obviously comes to a head; Dean figures out what's going on behind his back and confronts Sam about it, in a way that only Dean does," Ackles told Variety in regards to Sam's dealings with the Book of the Damned. "It's kind of the final straw - Dean knows that even if he forces Sam to stop helping Dean fight this, Sam's not gonna stop, and Sam's going to put himself in danger by not stopping... that unfortunately forces Dean to make some pretty dire decisions."

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Making "dire decisions" while under the sway of Cain's brand is probably not the best idea. A little hot headed to begin with, Dean is currently primed to explode.

Find out more when Supernatural airs Wednesdays at 9 p.m. ET on The CW. Click the video below to see a preview for the series' next episode, "Dark Dynasty."