WARNING: The following article contains spoilers for the Season 15 premiere of Supernatural, which aired Thursday on The CW.

Supernatural is back... and so is Jack! But, in true Supernatural style, there's a huge catch.

Considering actor Alex Calvert's face and name has been plastered all over the promotional material for The CW series' final season, his return shouldn't come as a surprise for fans. But, considering, as well, how things ended for him in Season 14, the nature of his resurrection was never going to be as clear-cut as Castiel -- or some other benevolent creature -- scooping his soul up and shoving it back in his body. In fact, Castiel even confirms this in the Season 15 premiere.

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As the Nephilim son of the Devil himself, whose human mother died so that he could live, Jack Kline's life was never going to be easy. Fortunately, he landed in the shared parental care of Castiel, Sam and Dean, who, despite their hesitancy about his satanic heritage, raised him the only way they knew how: in the family business.

Dean continued to have reservations about Jack's moral alignment but eventually warmed to "the kid," even giving him a coming-of-age driving lesson in the Impala. Unfortunately, things took a turn for the worse when Jack's soul began to be eroded away, while his extraordinary powers continued to grow. In a moment of uncontrolled frustration, he accidentally made Mary Winchester "disappear," and his misguided attempt to undo his mistake only made things cosmically worse.

As a pained Dean stood ready to put the bad kid down for good in the Season 14 finale, God, unable to resist interfering, turned up to do the dirty deed for him -- eye-melting and all. Season 15 picks up just after the wrathful deity throws the gates of Hell open, with vengeful spirits from Sam and Dean's hunting past flooding into the nearest vacant host bodies: corpses.

The gang, along with Jack's body, find refuge in a nearby chapel. As they desperately try to come up with a plan of escape, Jack suddenly stands up. Except, Jack's not home anymore. Like every other corpse in the area, Jack's body has been breathed new life into by a freed creature from Hell. In this case, a wise-cracking demon.

A furious Castiel demands he stop "defiling" his surrogate son's body, but the demon -- now sporting a pair of sunglasses to cover Jack's empty eye sockets -- claims he knows a spell that can help them. He's just an average working joe in Hell, you see, and he wants everything to go back the way it was. Using some graveyard dirt and angel blood, Demon Jack claps his hands and POOF! -- no more zombies. However, rather than vanquish the spirits, the demon simply blasted them further afield.

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As their job description requires, the group, along with their new demon helper, heads to the nearest town to begin the mammoth task of making a dent in the billions of Hell-bound spirits now terrorizing people top-side. Not to worry though because Demon Jack knows another handy spell -- one that can at least contain the threat in a particular area. While they clear out the ghost-infested town using fake FBI credentials and a fib about a burst pipe to put this plan into motion, Demon Jack uses some downtime with Dean to flirt with the uncomfortable hunter. He explains that people were "ugly" when he was a human, a time when people "worshipped a giant rock that looked like a penis." Safe to say Demon Jack is pretty old and pretty queer.

Whether or not the real Jack will return remains to be seen. And, with God no longer watching over the Winchesters with affection, that possibility seems far out of reach. Demon Jack, or "Crowley Jr." as Dean nicknames him, certainly seems like a helpful addition to Team (No) Free Will but, for a demon, he also he seems a little too helpful.

Airing Thursdays at 8 p.m. ET/PT on The CW, the final season of Supernatural stars Jensen Ackles, Jared Padalecki, Misha Collins, and Alexander Calvert.

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