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

Sam and Dean have encountered many of history's worst real-life villains during their hunting careers, from John Wayne Gacy to Adolf Hitler. But as of the second episode of Season 15, they can now add an even older one to that list.

The beginning of the episode finds Sam and Dean patrolling the border of the Kansas town where they've trapped the escaped souls of Hell -- trapped thanks to their newest ally: a demon named Belphegor who opportunistically hopped into Jack's vacant body when all of Hell broke (literally) loose. Dean is confident they can handle what's on the other side of the warding shield Belphegor put up. Belphegor is less confident, telling Dean these aren't your average "ghosty ghosts." Just to prove his point, when Dean blasts a spirit that suddenly appears with rock salt, demon informs him that he just shot Francis Tumblety, better known as Jack the Ripper.

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Dean's response to shooting one history's most notorious serial killers? "Cool!"

This is hardly the last we see of Francis. The murderer is soon up to his old misogynistic tricks, disembowelling one of the town's female residents who sneaks away from Sam and Castiel's watchful eyes. He also positions himself as the leader of the captured spirits, encouraging them to rally together and use their combined strength to break through the warding like kicking in a locked door. The situation soon escalates when he takes Kevin Tran and, later, Arthur Ketch hostage -- both of whom make surprise cameo appearances to assist the Winchesters. While Kevin is recovered without having too much damage done to him, Ketch isn't so lucky.

Francis uses Ketch as a human shield to get hold of the soul bomb -- renamed "soul catcher" by Dean -- that Rowena MacLoed (also making her Season 15 return) cooks up to vacuum up all the loose spirits. Dean is then forced to shoot Ketch to make Francis leave his body, allowing Rowena to recover the soul catcher and absorb Francis into it.

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Rowena Supernatural

This isn't her first encounter with the infamous killer, either. As we learn when the pair first meet each other in the episode, Rowena actually dated Francis when he was alive. Francis creepily compliments her for being special enough for him not to murder -- "I gutted my other dates" -- strengthening her resolve to get rid of him for a second time.

Though Jack the Ripper is gone by the end of the episode his influence still remains: We see a hundred spirits inside the warded dome clamoring to smash their way out, and with Kevin's warning that the magical defense is waning, it's only a matter of time before they do just that.

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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