Supernatural's Dean Winchester will go on a rampage in season 10's penultimate episode.

'Supernatural' Season 10 Spoilers: EP Previews Winchester's Lies, Jared Padalecki Makes A Shocking Comparison

It seems Dean (Jensen Ackles) will take his feud with the Stynes to the next level in "The Prisoner." "Dark Dynasty" will throw The Book of the Damned and the Styne clan back into the mix, and it seems the elder Winchester will not jump for joy at the chance become reacquainted with the devilish family.

"When it comes to the Stynes, Dean decides to take matters into his own hands," The CW teased. "Sam (Jared Padalecki) tries to come to terms with his decision."

'Supernatural' Season 10 Spoilers: Can Charlie & Rowena Crack The Book Of The Damned? 'Dark Dynasty' Plot Revealed

Sam's problematic decision may refer to his decision to keep the Book of the Damned from turning into a pile of fried human flesh during its eponymous episode. The tome may hold a cure for the Mark of Cain, but it also seems to cast a siren song over the Marks bearer. It remains to be seen whether or not Dean will succumb to its call before season 10 comes to a close.

"The Prisoner" will air on May 13.

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, "Angel Heart."