Supernatural's Dean Winchester is hiding somewhere inside his twisted demon persona, but Sam and Cas will have more than a little trouble trying to separate the two.

Castiel Uses Shocking Powers Against Dean On 'Supernatural', Will His Grace Hold Up?

Although Sam (Jared Padalecki) is well versed in the Men of Letter's demon cure, Demon Dean (Jensen Ackles) is unlike anything he has ever encountered. Between the Mark of Cain and Dean's current Shining performance, it won't be smooth sailing during "Soul Survivor."

"Sam's got to put Dean through a rigorous procedure to kind of get Dean back, and it is a procedure that doesn't quite go to plan," Ackles told Give Me My Remote. "It kind of backfires a bit so things get a little messy."

Demon Dean Is Boiling Mad In 'Supernatural' Sneak Peek; Lambastes Sammy During 'Soul Survivor' Cure

Although "messy" might be an understatement. "Homicidal" would be a better description considering Demon Dean will cap off the evening by swinging an ax at his little brother's head (see first video below).

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