A bride’s wedding night takes a sinister turn when her eccentric new in-laws force her to take part in a terrifying game.
The wealthy Le Domas family hosts a generations-long tradition of playing a game on the wedding night of the newest members to the family. This year, good son Alex is marrying a woman named Grace, and the game she ends up picking is Hide and Seek. What Alex failed to mention is his great-great-grandfather made a deal with a benefactor named Mr. Le Bail (who is all but outright stated to be the devil), and the family must deliver a sacrifice before dawn to save their lives. Grace only finds out after one unlucky maid is shot by Alex’s drug-addicted sister Emilie. Alex promises to help Grace get out.
Once the family realizes that Grace knows the truth, they try to figure out a way to go after her, while Alex is helping her escape. Two more maids get killed before the family’s butler, Stevens, makes his own move to get Grace. She almost succeeds in killing him once she gets out of the mansion, but Stevens catches her and tries to bring her back. Grace ends up causing Stevens to crash his car and kill himself, but she is found by Alex’s brother Daniel, and she is recaptured.
As the family prepares to sacrifice Grace, it is revealed that Daniel poisoned his family to give Grace a chance to escape. Unfortunately, Daniel is shot by his greedy wife Charity for letting Grace go. Alex’s father Tony tries going after Grace, only to get knocked out with a lantern that starts a fire. Mom Becky tries to kill Grace herself, but Grace beats her to death. Alex witnesses this, and after realizing Grace won’t stay with him now, he turns her over to his family.
The ritual resumes, but Grace manages to break herself free from the family’s grip. The sun rises, meaning the family has failed to hold up their end of the bargain. Just when it looks like the curse may not have been real after all, each member of the family starts violently exploding into bloody messes, ending with a weasely Alex trying to beg for Grace’s forgiveness. As the house burns down, Grace briefly sees the spirit of Mr. Le Bail, who appears to approve of her survival. She gets out and is found by police.
The wealthy Le Domas family hosts a generations-long tradition of playing a game on the wedding night of new additions to the family. In a flashback many years ago, young Alex Le Domas and his brother Daniel witness the killing of a groom who has just married a family member.
In the present day Alex marries a young woman named Grace at the family estates. That night it is established that Grace was a foster child and she feels family is important to have. Alex’s mother, Becky, thanks Grace for returning Alex to the family home as Alex and his family had been estranged for years. That night, as is tradition, the family orders everyone to the gaming room at midnight. Grace is required to draw a card from a mysterious wooden box and the card will indicate what game is to be played. Grace draws the card for hide-and-seek meaning she has to hide and everyone else tries to find her. What Alex failed to mention to Grace is that his great-grandfather Victor Le Domas made a deal with Justin Le Bail, a very wealthy man. If the family’s great-grandfather could figure out how a mysterious box (the same box Grace must use to select which game she would play) works he would become his wealthy benefactor who would help establish the family’s success and fortune. Included in the conditions given to Victor Le Domas, Mr. Le Bail demanded that, if hide-and-seek is chosen as a game from the mysterious box, the family must deliver a sacrifice before dawn or they will die. Alex is asked to wait while the family captures her so he is not so heartbroken and his sister-in-law Charity is supposed to keep watch of him. Charity stays outside the room Alex is in and he escapes the room though a servant’s passage way.
Grace only realizes the danger she’s in after a maid is accidentally shot and killed by Alex’s drug-addicted sister, Emilie. Alex finds Grace and promises to help Grace escape the estate grounds. Once the family realizes that Grace knows the truth, they scramble to capture her. Alex tries to help Grace escape by unlocking the house and turning on the house’s security cameras which are controlled by a central security room. The family rush to the security room and knock Alex unconscious handcuffing him to a bed. Alex explains to his mother Becky that if there is a choice between his family and Grace, Grace is who he chooses as she has made him a better man.
Two more maids are inadvertently killed before the family’s butler, Stevens, makes his own move to capture Grace but she hits him with a hot teapot and makes it out of the door Alex previously unlocked. Grace runs into a barn the family keeps with goats used as ritual sacrifices. There she encounters one of Emilie’s young sons who shoots her in the hand with a gun. She hits the boy which causes him to fall unconscious in the barn. She steps backwards and falls into a pit of skeletons and decaying bodies. As she climbs out of the pit, the ladder collapses and Grace manages to hang on by hooking her hand to a protruding nail via her gunshot wound. When Grace succeeds in getting out of the pit she runs to the far end of the property, bends a piece of the fence and escapes the property though a narrow opening, slicing her back in the process. Stevens, driving around the property looking for Grace, finds the opening and a piece of her torn dress and knows she has left the property. He hunts her down with his car and when he gets out to capture her a fight ensues. Grace is almost successful in killing him but chooses to leave and get in his car and drive away. She presses an “on-star” like help button inside the car to ask the operator to call 9-1-1, but the operator informs her the car has been reported stolen and shuts the car down. Now on foot again she is found by Stevens who shoots her with a dart gun and attempts to drive her back to the mansion. While on video call with the waiting family and listening to loud classical music, Stevens does not notice that Grace has woken up. She proceeds to kick Stevens repeatedly, causing him to crash his car and kill himself, but she is found by Alex’s brother Daniel. Although she begs him to let her go and says she believes he is a good person he knocks her unconscious with his gun and recaptures her.
As the family prepares to sacrifice Grace, they all begin vomiting and it is revealed that Daniel poisoned their wine to give Grace the opportunity to escape, realizing this tradition must end. As they recover, the hunt for Grace resumes. Daniel’s greedy wife Charity shoots him as he tries to protect Grace, who is able to overpower Charity and flee. Alex’s father Tony corners Grace, only to get knocked out by her with a lantern that starts a fire. Alex’s mother Becky shoots an arrow at Grace herself, but misses.
In an ensuing fight, Grace beats her to death with the mysterious box that dispensed the hide-and-seek card. After finally breaking the bed with his handcuffs Alex, now free, finds his bloodied and deceased mother and after also assuming Grace to have killed Daniel he asked if she will still stay with him. When it is clear to him that Grace won’t stay with him, and fearing death, Alex turns her over to his family. The ritual resumes, but Grace manages to break herself free from the family’s grip with Alex’s assistance, having changed his mind.
Suddenly, the family realizes that dawn has broken during Grace’s struggle, meaning they have failed to hold up their end of the deal with Le Bail. Just when it looks like the curse may not have been real after all, Helene attempts to violate the rules and murder Grace after the game has concluded only to explode into a bloody mess. One by one, each of the remaining family members follows suit. A cowardly Alex then begs for Grace’s forgiveness, saying he is still alive because Grace has made him a better man. When Grace requests a divorce and throws her ring at him, he also explodes.
As the house burns down, Grace briefly sees the spirit of Le Bail sitting in a chair, who appears to approve of her survival. At the end, Grace sits on the family mansion’s steps while it burns behind her and smokes a cigarette as first responders arrive. When one of the responders asks what happened, Grace replies “in-laws”.
1989 – Inside the Le Domas mansion, siblings Daniel (Etienne Kellici) and Alex (Chase Churchill) are running around while being followed by a man. Daniel hides Alex in a closet before he is approached by the man, Charles (Andrew Anthony), the new husband of the boys’ Aunt Helene (Elana Dunkelman). Charles pleads with Daniel to help him, as he has just been wounded and is being hunted. Instead, Daniel alerts the rest of his family to Charles’s presence. Helene tries to save her husband, but the family drags Charles into a room to his grisly fate.
Thirty years later, Alex (now played by Mark O’Brien) is getting married to a woman named Grace (Samara Weaving). She is nervous but eager to join his family’s gaming “dominion”, which is how they came about their enormous wealth. The couple go for a photoshoot prior to the ceremony, along with other members of Alex’s family. Daniel (now played by Adam Brody) is joined by his wife Charity (Elyse Levesque), who is open about the fact that she only married Daniel for his family’s money. Their father Tony (Henry Czerny) is visibly disapproving of Grace, but not nearly as much as Helene (now played by Nicky Guadagni), who shoots Grace a death glare. More approving is Alex and Daniel’s mother Becky (Andie MacDowell), who tells Grace that only Alex’s opinion matters. Moments later, everyone gathers for the ceremony, and Grace and Alex are married.
Later, Grace and Alex are trying to get intimate, but they are interrupted by Helene, who reminds Alex that he needs to join the family for something. Alex then explains to Grace that as per tradition with every new addition to the Le Domas family, she has to join the family for a game at midnight.
Grace and Alex reconvene with the family, who are now joined by Alex and Daniel’s cokehead sister Emilie (Melanie Scrofano), her husband Fitch Bradley (Kristian Bruun), and their sons Georgie (Liam MacDonald) and Gabe (Ethan Tavares). Everyone gathers around a table while one of the maids, Clara (Hanneke Talbot), is reading the boys a bedtime story. Tony explains to Grace that this tradition was started by his great grandfather Victor, who made a deal with a mysterious benefactor known as Mr. Le Bail. He granted Victor and his future generations their wealth, as well as a special box, while Victor was told to give his own part in the bargain. The family passes Grace the box to draw a card from it and pick the game. Charity said she got Chess, while Fitch got Old Maid. Grace draws Hide and Seek, and the room falls silent.
Tony instructs Grace to stay hidden until dawn in order to win, which does not sound appealing to her at all. As she goes to hide, the family arms themselves with guns, except for Helene and Fitch, who get an axe and crossbow, respectively. Grace goes to hide in a dumbwaiter, and Alex chooses to sit this out. As the family goes off to find Grace, Alex leaves his room to go warn her, which Charity finds out about. Grace leaves the dumbwaiter and wanders before she is found by Alex, who covers her mouth and tells her to be quiet. Clara is walking around, as Georgie has gotten out of bed. As she looks for him, a gunshot rings out, and Clara’s face is blown off. Emilie fired the shot, thinking it was Grace, but she realizes her error. Tony, Helene, Daniel, and Becky come in to help move Clara’s body. Grace sits in horror at what she just witnessed. Alex pulls her into another room to explain the truth to her. Hide and Seek, for the Le Domases, means that they think they need to hunt Grace and kill her before dawn, or else they will die. Alex admits that he didn’t tell her about this because he feared that she would leave him, but he promises to find a way to get her out safely.
Grace trades her heels for tennis shoes and tears off the bottom of her dress to move around more easily. She starts to walk out but is immediately spotted by Tony, Helene, and Daniel. They try to incapacitate her, but Emilie, fresh off another line of coke, starts wildly firing at Grace and misses. She runs for it, and the others realize that Grace knows the truth now. She is also found by Daniel, but he could not care less about the hunt, so he gives Grace a headstart before alerting everyone.
The family gathers together to come up with a new plan, when another maid, Tina (Celine Tsai), comes in trying to tell Tony that she saw Grace. Emilie, who was given Fitch’s crossbow, accidentally fires an arrow through Tina’s head. Helene chops Tina’s head off when she won’t stop groaning. She then suggests to Tony that they turn on the cameras to locate Grace, but Tony is against it since it’s not part of the tradition.
Grace finds a rifle and ammo, and she loads up. She hides in the kitchen while Alex tries to turn on the cameras and disable the locks on the doors and windows. The butler, Stevens (John Ralston), enters the kitchen to make tea. He hears Grace loading her rifle, and she is soon spotted. She tries to shoot Stevens, but he tells her the ammo is just for display. This doesn’t stop her from smashing the teapot over his face and managing to evade him. Alex succeeds in unlocking the doors and windows, and Grace manages to get outside. Tony and Daniel find Alex in the control room, and Tony attacks him. Alex fights back but is talked down by Daniel, which only gives Tony a chance to knock Alex out. They handcuff Alex in his bedroom to prevent him from helping Grace. Meanwhile, she is outside on the roof but can overhear Tony and Helene talking. They know Alex has always rejected their tradition, being the “good son”, but Helene thinks that Alex will come to accept his place in the family like she did when Charles was killed. She tried to fight it at first, but then realized she should have killed him herself, and she believes Alex will eventually follow in his family’s footsteps.
Grace is almost out of the house when she is spotted by the third maid, Dora (Daniela Barbosa), who is hiding in the dumbwaiter. She tries to call out to the family now that she has found Grace, but Dora then accidentally shuts the dumbwaiter, causing her to be crushed in it. Grace then flees once again.
Grace makes it outside and runs to the stable. She sees Georgie walking there and thinks he will help her, but he draws a gun on her and shoots a hole through her hand. In response, she punches him in the face and knocks him out cold. Grace is then startled by a goat, leading her to fall into the Goat Pit, where the corpses of goats and unlucky family members are disposed. Grace climbs up to the top as the ladder starts breaking under her feet. She reaches the top but has a nail go through the hole in her hand. She manages to muster up the will to pull herself out, and then use part of her dress as a bandage. She runs back outside and manages to break through the front gate. She tries to flag someone down, but he is a prick and drives away from her. Not long after, she is found by Stevens, who tries to capture her. Grace fights him and attempts to strangle him with a piece of her dress. She takes his car, but doesn’t see that he is still alive.
Becky orders Daniel and Emilie to dispose of the maids in the Goat Pit, since the others think they have been doing more harm than good to the hunt. Daniel is fed up with the family, but Emilie is adamant in sticking to the tradition so her boys won’t be hurt.
Grace drives Stevens’s car away and talks to a customer service agent, Justin (Nat Faxon), to get help. Unfortunately, since the car was already reported stolen, Justin shuts the car down, which leads to Stevens finding Grace and tranquilizing her. He drives back toward the mansion while video-chatting with the family to let them know he has Grace. He starts to play classical music over the radio and doesn’t see Grace waking up, but the family does. They try to warn Stevens, but he doesn’t see Grace as she kicks him twice in the head, causing him to roll the car over into a field. Stevens is dead, but Grace survives. She gets out and is found by Daniel. He says he can’t let his family down, so he knocks her out and takes her back to the mansion.
Becky goes to Alex’s room to try and talk to him. She thinks that while he loves Grace, he will ultimately stick to his family’s wishes. Alex tells her that he will kill her if anything happens to Grace.
The family places Grace on an altar to begin the ritual to sacrifice her to Mr. Le Bail. They pass around a chalice and drink from it, but then they start violently puking just before Tony kills Grace. Daniel gave everyone something to make them sick, and he frees Grace from the altar. He tries to help her get out, but they are found by Charity. Knowing that he is no longer on their side, she shoots Daniel in the throat. Grace fights Charity and takes the gun from her. The bullets are gone, so she pistol-whips Charity. Grace tries to help Daniel, but he tells her to go. Alex breaks free from his cuffs and finds Daniel dying. He tries to save his brother, but it is too late. Tony then goes for Grace and tries to kill her himself, but she hits him over the head with a lantern and drops it, causing the curtains to catch fire. Grace is then found by Becky, who misses with her arrow but then tries to strangle Grace. Grace pulls the tablecloth down and grabs Mr. Le Bail’s box, and she knocks Becky off of her before bludgeoning her to death with the box. Alex then comes across the scene and tries talking to Grace. He realizes that she will never stay with him now, so he turns on her and gives her up to his family.
Everyone continues with the ritual by holding Grace down themselves. Just as Alex is about to plunge the dagger into his wife, Grace breaks Helene’s grip by clawing her hand, before letting the dagger go into her shoulder. She gets off the table and holds the dagger toward the family while screaming. They then see that the sun has come up, meaning it is now too late. As they recoil in horror for their impending death, nothing happens. However, Helene plans to kill Grace anyway. She grabs the axe, when suddenly…BOOM! Helene explodes into a bloody mess. The family realizes that they really are screwed. Fitch explodes next, followed by a begging Charity. Emilie tries to get away with Georgie and Gabe, but they all burst too. Tony tries yelling about how he followed the rules, but he turns into paste as well. Alex then tries to weasel his way into getting Grace’s forgiveness, but she hands him her ring and says she wants a divorce. BOOM goes Alex. The fire from the curtains then spreads around the house, and for a brief moment, Grace sees the spirit of Mr. Le Bail sitting in his chair, and he nods approvingly to her.
Grace exits the burning mansion, now covered in blood. She sits on the steps to smoke a cigarette, just as police and paramedics arrive. An officer asks Grace what the hell happened, to which she simply replies, “In-laws.”