What Will It Take to Stop Jack on 'Supernatural'?

Meredith Jacobs
Spoiler Alert Diyah Pera/The CW

[Warning: The below contains MAJOR spoilers for Season 14, Episode 19 of Supernatural, "Jack in the Box."]

The "Jack in the Box" in Thursday's episode of Supernatural isn't the fun kind you'd show your kids.

Even if it was an accident, Jack (Alexander Calvert) still killed Mary (Samantha Smith). Now, Sam (Jared Padalecki) and Dean (Jensen Ackles) have to figure out what to do about him.

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Duma (Erica Cerra) recruits Jack to make more angels for heaven and attack those who appeared to be fake believers. Once the Winchesters realize what he's doing, Dean knows that, while he can't be killed, Jack can be contained.

Dean's plan is to put him in the Ma'lak Box. He built the box when he had Michael trapped in his head. The coffin can contain anything, including an archangel. But is it strong enough to contain Jack? Furthermore, Jack has to get into it willingly, and that means Sam must convince him they're working on a spell to fix his soul. (No such spell exists.)

(Diyah Pera/The CW)

"You've always been in his corner," Dean explains to his brother. "If I do it, after what happened to Mom. I could lose it. I will lose it."

Sam prays to Jack, and he joins them in the bunker. Sam and Dean are wary in their approach to Jack as he tells them he "regrets" the "accident."

"She kept talking about my soul, that I didn't have a soul, and she kept pushing," Jack says. "I didn't want this no-soul thing to become an issue between us. I guess I snapped. Before I knew it, it was all over."

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They tell him they want to keep him safe so no one else gets hurt while they work on fixing his soul, and it works. Jack does get into the Ma'lak Box of his own volition, but then his subconscious, in the form of Lucifer (Mark Pellegrino), tells him that Sam and Dean aren't planning on letting him out.

"You're no longer useful to them," Lucifer says. "You killed their mother. There's no coming back from that." Jack's going to be in the box forever.

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Are they going to keep him in there forever? Dean's ready to, but Sam's hesitant. When Castiel (Misha Collins) returns to tell Jack that Duma was manipulating him, he disagrees with the Winchesters' plan.

But it doesn't matter what any of them say at that point. Jack uses his powers to break free from the box. If that can't contain him, do they have any hope of stopping him?

(The CW)

The Season 14 finale promo makes it look like Dean may find a bullet that can stop him, but will he pull the trigger? Or is the trailer misleading viewers? What's in that gun?

Perhaps we should take into account an exchange between Sam and Dean in "Jack in the Box." Sam had hope that it wouldn't end poorly with Jack, while Dean always saw it as a "long shot" that things would work out.

"Yeah, but long shots are kind of our thing," Sam says. Will that be the case this time?

Some fans have hope that this won't be the end of Jack.

However, others are worried about what may happen after Sam and Dean manipulated Jack, just like Duma.

Supernatural, Thursdays, 8/7c, The CW