Supernatural's Dean Winchester and the now human Castiel will reunite once more in tonight's "Heaven Can't Wait."

On the lamb from a cohort of revenge seeking fallen angels, Cas (Misha Collins) has attempted to assimilate in the human world by picking up work at a Gas-N-Sip. However, when he notices an angel related pattern in some recent murders, the former angel will call up the Winchester brothers for help.

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Meanwhile, Dean (Jensen Ackels), Sam (Jared Padalecki), and Kevin (Osric Chau) are hunkered down at the bunker attempting to decode the angel tablet. The elder Winchester will leave his angel-possessed brother behind with Kevin and Crowley (Mark Sheppard) when he decides to answer Cas' call.

However, things won't be all sunshine and rainbows between the hunter and his once angelic friend.

"First of all, Cas is pissed at Dean and rightfully so," Collins told TV Guide. "He's feeling a bit jilted for having been thrown out on his butt."

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Dean, on the other hand, is still dealing with the remorse he feels after following Ezekiel's instructions to keep Cas at a distance.

"[Dean feels] a fair amount of guilt at sending [Cas] packing," Ackles explained to TV Guide. "Obviously he'd much rather have Cas around. The family that Dean knows is very, very small and getting smaller."

Unfortunately, Cas' hunting abilities have not improved with the removal of his grace.

"Now you just have an awkward human being with Dean, who's very comfortable in these shoes and totally understands walking into a crime scene. But you get awkward boy over here doing it all wrong," Ackles said, according to TV Guide. "It makes for some good comedic moments."

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Check out some stills from episode stills below courtesy of Spoiler TV and click on the video below to see a preview of "Heaven Can't Wait."

Supernatural airs Tuesdays at 9 p.m. ET on the CW.