Supernatural's Jensen Ackles wasn't kidding when he hinted that Dean may take a trip back to purgatory in "The Werther Project."

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The elder Winchester will drop into purgatory during episode 19, and the hunter will meet up with the deceased-revived-deceased vampire pal Benny (Ty Olsson).

"Guess the vamps outta the coffin," Olsson tweeted on Friday.

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The reasons for Dean's (Ackles) trip to Monster heaven (monster hell?) is unknown, but it will undoubtedly have to do with Sam's (Jared Padalecki) next attempt to cure the Mark of Cain. Magnus, the Men of Letter's former Master of Spells, curated his own collection of magical artifacts following his expulsion from the MOL, leaving behind a mysterious magical box that could hold the key to removing Dean's demonic brand. Unfortunately, the Winchesters' meddling will set of a deadly alarm system with unknown consequences.

Dean's trip to purgatory won't be the only unsettling development during "The Werther Project" - Sam will apparently team up with Rowena (Ruth Connell).

Scroll through the photos above to find out more about the April 22 episode.

Supernatural airs Wednesdays at 9 p.m. ET on The CW. Click the video below to see a preview for the series' next episode, "Book of the Damned."