WARNING: The following article contains spoilers for Season 15, Episode 3 of Supernatural, "The Rupture."

We're only three episode into Supernatural's final season and, already, fan-favorite characters are dropping like flies.

As Sam, Dean and their allies hurry to plug up the door to Hell God ripped open that's been leaking bad spirits since the Season 14 finale, the cost of their endeavors reaches heartbreaking heights in "The Rupture." We've been warned that the deaths this season are "permanent," which only making this week's casualty list particularly maudlin.

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ARTHUR KETCH

Arthur Ketch Supernatural

The man that Dean once described as a "low-rent Christian Bale" was the first victim of the episode -- and we're sorry to say that it wasn't your peaceful, died-in-his-sleep kind of ending. (A hunter should be so lucky.) Waking up in a hospital bed after surviving a ghost-repelling gunshot wound from Dean in Episode 2, the ex-British Man of Letters immediately leaps into action to come his friends' aid once more.

Ketch is stopped by the surprise appearance of the demon, Ardat, who contracted him to assassinate another demon, Belphegor -- currently wearing Jack as a meat suit. Ketch's failure to fulfil the job invokes her anger and, after he refuses to give up Belphegor's location to protect Sam, Dean and Castiel, the demon is only further incensed: ripping his beating heart from his chest.

ROWENA MACLEOD

Ketch, who had been a fairly central character to the show since Season 12, was a sad loss. However, the next one hits even harder. Rowena answered the boys' call in the previous episode, bringing her vast knowledge and command of witchcraft with her to the town that the group magically trapped all of Hell's escaped spirits in.

With the barrier Belphegor put up rapidly failing, fear sets into Rowena when she senses how strong the ghosts' collective rage is -- strong enough for them to scratch away at the shield until it falls. Then, Belphegor has another brainwave: he and Castiel travel to Hell to pick up an old relic belonging to Lilith -- a demon siren, of sorts, called Lilith's Crook -- while she and Sam create an enchanted "bomb" that will seal the tear once all the spirits have been called back inside by the Crook.

As is so often the case in Supernatural, things don't quite go according to plan. The rupture begins to close, but a fight between Belphegor and Castiel leads to the Crook's destruction. Rowena realizes that nothing short of laying her own life on the line will work now. She tells Sam that their final Hail Mary is to use her own body as a vessel to suck all of the spirits into, at which point she'll seal herself in Hell. Of course, Sam balks at the idea of her self-sacrifice, but Rowena reminds him of the prophecy in Death's archives that her "true" death has to come at his hands. As a firm believer in magic and destiny, Rowena begs him to end her life on her own terms.

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Tearfully, Sam complies. The last we see of the all-powerful witch is her body gracefully tumbling into the gaping Hellmouth just in time for it to seal itself up.

HONORABLE MENTIONS: JACK & CASTIEL

These aren't major character deaths, per se, but they are good-byes. (For now, a least.) Once Castiel learns that Belphegor's plan this whole time was to use him to obtain Lilith's Crook -- and use it to rule everything with a body juiced up on souls -- he turns on the demon. It doesn't help, of course, that the trickster is wearing the face of someone Castiel openly admits was like a son to him, and his revealed treachery is the only ammo Castiel needs to smite him. With this, Jack's original body is now gone, making a potential revival for the Nephilim possibly even harder.

Dean is furious to discover what Castiel did, particularly as it led to Rowena's death. The angel's forlorn defense that "something went wrong," fails to pacify the older Winchester brother, who cuts him right down to size: "Yeah? Well, why does that something always seem to be you?"

"You used to trust me," Castiel replies. "Now you can barely look at me. [...] I'm dead to you." He points out that his powers have been failing and Dean has been totally despondent to him since Mary's (second) death because he still blames Castiel for it. "I don't think there's anything left for me to say. Jack's dead; Chuck's gone; you and Sam have each other. I think it's time for me to move on."

And with that, the third honorary Winchester brother walks out of the Bunker without so much as a word of protest from Dean, adding to the heavy toll that has come with this episode's big win.

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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