Supernatural's Castiel is dying, but the angel will devote his remaining energy to saving Dean Winchester in season 10.

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Devoid of his original grace, Cas (Misha Collins) is quickly burning through his stolen angel juice. While saving himself is probably still high on his to-do list, Cas will be more concerned with Dean's (Jensen Ackles) fate when the series returns this fall.

Last Cas knew, Dean had died at the hands of Metatron (Cutris Armstrong). Once he learns his buddy was transformed into one of hell's most powerful demons (see video below), Cas will pull out all the stops in order to restore the hunter's humanity.

Castiel Ready To Kill Demon Dean On 'Supernatural', Prepares Sam For Worst Outcome

"It's tough, it's tough. It's a challenge when your friend becomes a demon. Cas is very concerned about getting Dean fixed. He wants to get him fixed," Collins explained at NJCon last weekend before getting a laugh out of the double meaning of 'fix.' "Spay or neuter your hunter..."

While Cas and Sam (Jared Padalecki) are busy tracking down the elder Winchester - who is working really hard to keep them off his trail, by the way - Dean will embrace his new powers and raise a little hell with Crowley (Mark Sheppard). As Sheppard puts it, Castiel's friend is now his "bestie."

Considering this pairing and Dean's actions over the hiatus, however, Cas' won't be blind the possibility that he may have to put the new demon down.

"Even though it might be hard to hear, it might be hard to say, he tells Sam, 'Listen, you know what you have to do if things don't go right,'" Ackles told TV Line.

Find out how Sam and Cas will restore Dean's humanity - and Cas' grace - when Supernatural returns to The CW on Oct. 7.

Tags: supernatural television the cw