WARNING: The following article contains spoilers for Season 15, Episode 2 of Supernatural, "Raising Hell."

We've been promised many returning faces for Supernatural's final season -- including a long, lost Winchester brother -- and just two episodes in, three fan-favorites have come along all at once.

The first was to be expected: Rowena MacLeod. Mother of the former crossroads demon-turned-King of Hell, Crowley, and a powerful, ancient witch in her own right, between Seasons 10 and 15 Rowena evolved from a prickly antagonist to one of the Winchesters' most useful allies. Whenever Sam and Dean are in need of magical assistance, Rowena is always their first port of call, and despite her grumbling, she almost always comes through for them.

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This is exactly how the spellcaster gets pulled into the action in "Raising Hell." The town in Kansas where Sam, Dean, Castiel and their demon helper, Belphegor (hijacking Jack's body), have kept all of the escaped souls from Hell contained needs a permanent solution. Sam remembers the "soul bomb" -- or, "soul catcher," as Dean re-dubs it -- that Rowena created by sucking up souls to combat The Darkness and figures that could well be the answer. Sort of like a dust buster for spirits. Rowena is doubtful she can match the original's power but she goes through with it anyway. And, thankfully, the soul catcher does an adequate job.

Rowena Supernatural

The second cameo appearance is more surprising: Arthur Ketch. Like Rowena, Ketch is an enemy-turned-ally of the Winchesters. Also like Rowena, the former member of the British Men of Letters provides an important set of skills; except his aren't magical, they're analytical. (A yin and yang dynamic that quickly has sparks flying between the pair.)

Ketch's knack for crafting modern-day weapons against the supernatural is demonstrated by his explosive entrance: blasting iron flakes into a ghost from a shotgun. Though at first, he claims he was just in the right place at the right time, upon being introduced to Belphegor, Ketch admits he's actually in town because of the escaped demon. Another demon called Ardat contracted Ketch to assassinate Belphegor -- a fact Belphegor isn't that shocked by.

Ketch lends the Winchesters his assistance with the upstart ghosts trying to break the warding keeping them trapped in the town. For his trouble, he earns himself a shotgun wound to the chest after being possessed by their leader and leaves town on an ambulance stretcher, his contract unfulfilled.

Arthur Ketch Supernatural

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The final cameo of the episode is the most unexpected of the three: Kevin Tran. Kevin's young life took a dramatic turn when he was tapped to become a prophet of the Lord. The role saw him do a lot of good, like helping in the fight against the Leviathan and using the Demon tablet  to uncover a way to permanently shut the doors to Hell. However, like most of the Winchester's friends, Kevin met a grisly end.

His appearance in "Raising Hell" means he also didn't fare any better in death. Instead of being sent to Heaven by God, as was assumed, Kevin's soul actually wound up in Hell, a revelation that further solidifies the deity's villainous status. However, Kevin boasts that his time underground actually puts him in a good position to once again help Sam, Dean and Castiel out: "Since God himself sent me down, I've got kind of a bad boy rep'."

When Dean sends Kevin in amongst the ghosts as a mole, however, it appears he may have been exaggerating. Instead of welcoming him, the rebellious evil spirits hold "whiny Kevin Tran" hostage. The gang is able to rescue Kevin in the end, and he starts to issue his good-byes. Dean protests that they need to find a way to get Kevin into Heaven but, without God's executive authority, Belphegor claims its impossible for a soul condemned to Hell to be taken in by Heaven.

This leaves poor Kevin trapped between a rock and a hard place: he can either be tortured in Hell or go insane aimlessly wandering around Earth. He chooses the latter, leaving things on a bittersweet note.

We already know Rowena will be sticking around for longer, but this probably isn't the last we'll see of Kevin Tran or Arthur Ketch, either.

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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