Sam's (Jared Padalecki) desperation to save his brother Dean (Jensen Ackles) from a witch's spell will lead him to an unlikely savior in the next episode of "Supernatural" season 12.

In the episode titled "Regarding Dean," Sam's older brother will encounter an ancient, powerful family of witches who seem to be unpleased to meet him. Their fury will prompt them to cast a spell on Dean that will erase all his memories in a haste.

Executive producer Andrew Dabb revealed in an interview with TVLine that Dean will be "trapped in a Memento-type loop, where he's kind of losing his memory a little bit" in the upcoming episode.

"For him, as someone who struggles with all the baggage from years and years of doing a very, very difficult job, it almost becomes freeing, in a way. So you're going to see a Dean that is a lot more fun and childlike," the executive producer also said.

Dabb also teased that Dean's condition will be emotionally tragic, especially when he begins to forget his own brother and himself.

If Sam will not act fast, his brother will completely forget everything about him. To stop the effect of the spell, Sam will ask Rowena (Ruth Connell) to help him in his quest.

This will not be the first time that the Winchester brothers will rely on Rowena's powers for help. She was the one who assisted them in removing the Mark of Cain from Dean by decoding the Book of the Damned in season 10. The witch agreed, but she demanded that they must kill her son Crowley (Mark A. Sheppard) for her.

Rowena was last seen in season 12 episode 8 titled "LOTUS," when Crowley helped her eliminate her opportunist new fiancé.

The next episode of "Supernatural" season 12 airs on The CW on Thursday, Feb. 9.