Supernatural's Castiel doesn't have much angel juice left, but the Winchester's pal will pull out all the stops when it comes to fixing up Demon Dean in "Soul Survivor."

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Dean (Jensen Ackles) will soon be cured of his black eyes, and the rebel angel will pop by to help Sam (Jared Padalecki) complete deal with the transition. Unfortunately for Dean - and for Cas' (Misha Collins) failing grace - Sam will need a little help wrangling the demon.

"It's a pretty strenuous meeting," Ackles said, according to TV Line. "Dean is still not quite Dean, and Cas is having to, unfortunately, use some powers he would rather not have to use against Dean."

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Despite his own problems, Castiel will be determined to ensure the Cure takes, not resting until Dean is back to his old self, or at least Mark of Cain Dean.

"Castiel is hellbent on ridding Dean of his demon and willing to do anything, no holds barred, to make sure he's no longer a demon," Collins explained to TV Line.

Find out more when Supernatural airs Tuesdays at 9 p.m. ET. Click the video below to see a preview of the series' next episode.

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