WARNING: The following contains spoilers for Ready or Not, in theaters now.

The trailer for Ready or Not, the black comedy horror film, made it obvious the Le Domas family would go to hunt Samara Weaving's Grace on her wedding night as part of some sadistic ritual. However, the footage depicted that her new husband, Alex (Mark O'Brien), was on her side.

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While it seemed they'd be on their own in this game of predator and prey, the film's final act offers Samara a surprising villain, as it's Alex himself who betrays her, shocking audiences as he tries to help his family to finish the job.

ALEX, THE HERO

Alex and Grace hide behind a bed in Ready or Not

Grace is targeted because the Le Domas family wants to sacrifice her to Satan after she drew the hide-and-seek card after the wedding. It's tradition to play games, but this death card is a means to repay the devil for offering wealth to the family. But from the get-go, Alex tries to save his new bride, offering clues about where to hide and attempting to switch off the house's security lockdown so Grace can escape, only for him to be incapacitated by his own family.

Alex had no choice but to marry Grace because, even if they eloped or simply lived together, the devil would drain her life essence as they forged a bond through love. He hoped she'd draw another card from the box Satan sent to the family, and that instead play a boring board game like his siblings' spouses had. But, alas, things don't go according to plan, leaving him chained in his bedroom while Grace tries to survive.

A HUSBAND SCORNED

In the finale, Alex's brother, Daniel (Adam Brody), ties to help rescue Grace by poisoning his family during the sacrificial ritual, only to be killed by his own wife. Grace kills her in return, but as she tries to escape, she also has to beat Alex's mother, Becky (Andie MacDowell), to death with the box. Alex frees himself and, after seeing his brother and mother dead, tries to embrace Grace, only for her to rebuff him.

She's angry that he involved her in this ritual, and he selfishly tells her that if he had told her about the game, she would have left him. He simply held on to the hope she wouldn't draw the death card. However, a sickened Grace wants nothing to do with him and his bloodline. At that point, Alex makes a stunning heel turn, and restrains her so the ritual can continue. With the baton passed to Alex, and Grace needing to perish by dawn or else his family will, he tries to stab her to death.

BLOODY KARMA IS SERVED

Samara Weaving smiling and covered in blood in Ready or Not.

Luckily, the wily Grace fights him off and, as dawn arrives, the man we thought was a hero finds himself facing a bloody fate. One by one, the family members, including children, start to explode in the occult room, splattering guts all over the bride. The prophecy of failure was true, and they're paying the price. But Alex begs Grace's forgiveness so he can live. She laughs him off, telling him she want a divorce as she gives back the wedding ring, and watches him as he explodes.

It's the price for falling back in line with his demented family, creating one of cinema's goriest endings. As Grace surveys the damage in her now-crimson dress, she sees the ghost of Le Bail, the merchant Satan used to offer the Le Domas family the box centuries earlier, and acknowledges amid all the violence, every death was worth it so she could have her freedom.

Directed by Matt Bettinelli-Olpin and Tyler Gillett and starring Samara Weaving, Mark O'Brien, Adam Brody, Henry Czerny, Andie MacDowell, Kristian Bruun, Melanie Scrofano, Nicky Guadagni and Elyse Levesque, Ready Or Not is in theaters now.