Supernatural's Sam and Dean are cooking up a recipe for disaster.

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Temporarily put on the back burner, The Winchester boys recently reignite their lying game, a move that rarely ends well for the hunters.

"At the end of our last episode we saw Sam sitting down with Rowena and making what looked like something of a devil's bargain to find a way to cure Dean," executive producer Jeremy Carver said in a "Werther Project" preview. "There is still this deceit and secret that started to purvey the relationship. Dean thinks it's a standalone case while Sam knows that there is something more to this case, which, even by episode's end, he's still not telling his brother."

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Sam (Jared Padalecki) and Dean (Jensen Ackles) are no strangers to secrecy, and both Winchester brothers will soon start to play their cards close to their chests. Carver indicated that Dean will still be in the dark about the survival of the Book of the Damned by time Wednesday's episode comes to a close, meaning the elder Winchester also won't know of Rowena's (Ruth Connell) involvement in the whole affair.

Sam is going out on a limb trusting Rowena, and the uneasy partnership contains a dangerous dynamic that Padalecki compared to the misguided trust Sam put in a certain infamous demon.

"She's almost like Ruby in season four, where it's like, 'I haven't seen you do the bad that I've seen Crowley do, so I'm more likely to trust you,' and once you trust somebody like that, you're opening yourself up for a lot of problems," Padalecki told Variety.

Find out what's next for Sam and Dean when Supernautral airs Wednesdays at 9 p.m. ET on The CW. Click the video below to see a preview for "The Werther Project."