Late in the evening, Abigail is practicing ballet in an empty theater. Meanwhile a group of criminals is getting ready to strike. The hacker shuts down all the security cameras in Abigail’s house and the sniper climbs on the roof.
When Abigail leaves the theater, her driver gets her on the car, unaware the criminals have put a tracker under it. As soon as the car gets moving, so do the kidnappers. The hacker opens the house’s doors and three of the criminals sneak into Abigail’s bedroom to hide behind the furniture.
The woman realizes they’ll be kidnapping a child and protests since she usually doesn’t mess with kids, but the others tell her to deal with it. Soon Abigail arrives home and gets on the bed, so the criminals use the chance to attack. A guy tries holding her down, but Abigail stabs his hand with a pencil.
The other man takes over and covers her mouth as he captures her while the first guy tries to punch her, but the woman stops him from hurting a kid. Then she injects Abigail with a sedative to put her to sleep. The other half of the team is waiting outside and warns those in the house that there’s a car incoming.
While the sniper keeps the incoming car under his watch, the trio hurries to put Abigail in a bag and sneaks out through a window. As they cross the garden and reunite with the sniper, the alarms activate and they have to run. Fortunately the last two criminals pick them up just in time and they escape without issues.
During the ride, they check Abigail’s pulse to make sure she’s fine and blindfold her. When they’re about to reach a traffic, the hacker tells the driver to take a different road, but the driver makes a sudden turn and hides the van behind a big truck. Eventually they make it to their destination, which is an old abandoned mansion outside the city.
There they meet with Lambert, the guy that hired them. After they handcuff Abigail to a bed, Lambert reminds the group of the rules. They mustn’t share any names or backstories, and they should avoid getting naughty among themselves.
It’s a twenty-four-hour job, so they must babysit Abigail until her rich dad sends the fifty million dollars. Lambert doesn’t tell them who the dad is, but he does collect everyone’s phones to avoid getting tracked. Before leaving, Lambert gives each team member a codename inspired by the Rat Pack.
Afterward the team begins enjoying all the drinks in the house. Joey refuses to share her candy with Dean, who pretends to be smart and tries to guess everyone’s backstory, but he fails. When Joey mocks him, the others bet some money to see if she can do better, and by reading their body language, clothes, and personalities she guesses all correctly.
Frank used to be a detective, Peter is a dimwitted mob enforcer, the hacker Sammy comes from money and is doing this for fun, Rickles is a former marine sniper, and Dean is a sociopath driver. In return, Frank concludes Joey is a recovering addict. Then Joey checks on Abigail, who complains the blindfold is too tight.
Joey covers her face and takes the blindfold off, she also notices that the handcuffs are hurting her so she re-cuffs her hands in front. Since Abigail is crying, Joey explains they won’t hurt her and they only want the money, so Abigail makes her do a pinky promise. Joey shares she has a son, and in return Abigail tells her that they made a mistake because her father doesn't care about her.
When Joey’s about to leave, Abigail says she’s sorry for what's going to happen to her. Worried, Joey rejoins the group and tells Frank that Abigail’s father may be a violent man. Frank dismisses it as Abigail trying to make Joey feel bad, but once everyone is distracted, he goes to check on the child.
He’s shocked to see her without the blindfold and immediately covers his face while pointing his gun at her until she swears she didn’t see him. Then Frank presses her until she says her dad is Kristiof Lazaar. Freaking out, Frank runs back to the group and announces that he’s leaving.
The others demand an explanation and Frank explains that the girl is Kristof Lazaar's daughter, a very dangerous and powerful crime boss. Joey and Rickles also recognize the name and share Frank’s worry. An argument ensues on how to proceed and in the end they decide to stay to get the money, which they can later use to escape and start a new life far from there.
They agree to keep an eye on the perimeter and keep all doors closed. Later Joey is looking around the house, following a noise that is just an open window. While opening it fully to stop the noise, she sees an old statue of a father and his child.
Then she bumps into Rickles, who tries to flirt with her and fails. He also tells her that he doesn't trust the others and they agree to watch each other's backs. Meanwhile Sammy finds a room with TV and is suddenly startled by a presence behind her, but it’s just Dean playing a prank.
He has the nerve to try flirting with Sammy, who furiously kicks him out. Then Dean finds a sleeping Peter and draws a man’s member on his face. He keeps wandering around the house and enters a dark corridor with tons of old pictures, including one with a girl that looks a lot like Abigail.
Next he goes to the basement kitchen, where a door opens by itself. Confused, he enters the room and gets startled by a rat. As he tries to leave, suddenly an unseen presence grabs him by the legs and pulls him back.
Sammy hears his screaming and goes to the basement, where she finds Dean sitting at the table. When she tries to approach him, his head falls and Sammy screams before puking. Soon the others make it to the basement too and they agree Sammy doesn’t have the strength to do that.
In fact it reminds them of the stories about Lazar's hit man called Valdez. Several years ago, three top members of Lazaar’s gang were captured by the FBI. The night before their trial, they were kept hidden on the top floor of a hotel with agents guarding every corner.
The next morning, the FBI stormed in and found their bodies with their heads cut off and no organs. There was no way in or out of the room except for the door on the 23rd floor. Getting worried, they decide to check on the girl and find her well in the room.
Rickles is still scared of Valdez and wants to leave, but when he opens the front door, they’re shocked to discover another barred gate. Peter tries to push it open to no avail, and this triggers a security system that covers all the windows, meaning the group is now stuck inside. Joey concludes this is at trap and Rickles runs to check on his weapon, only to find it gone.
Joey rushes to Abigail and asks if she’s seen anybody else besides her and Frank, but Abigail swears she hasn’t. She also shares that Frank threatened to harm her, that he said he worked for her dad, and that his real name was Valdez. Afterward Joey meets with Rickles and they both share what they know, concluding it doesn’t make sense.
They agree to look for a way out, but as Joey tries to leave the room, she hears a noise. Rickles is standing rather awkwardly, so she goes to check on him and is horrified to discover that he’s been severely injured. His dead body falls in her arms and she puts him down before rushing downstairs.
A furious Joey aims her gun at Frank, accusing him of being Valdez and killing Rickles. Frank pulls out his gun too and says Joey’s letting Abigail manipulate her. He asks Peter to do something about Abigail, so Peter goes to the room to kill her.
Before he can shoot, Joey arrives and quickly disarms him. Sammy and Frank also come and an argument ensues. Meanwhile Abigail easily removes the handcuffs and stands up, using a ballet move to show her true face: she’s actually a vampire.
Abigail jumps on Peter and is about to bite him, but Frank shoots her down. To everyone’s shock, Abigail just sits up as the wound heals itself. Joey shoots her too but it’s clear that bullets do nothing, so they run and lock the door.
The group discusses what to do as they realize Abigail was Valdez all along. All the doors are equipped with magnetically sealed locks and shutters two inches thick, so they can't be broken and Sammy doesn’t have the equipment to hack them. Everyone’s tense and when Peter asks them to slow down, Frank grabs him by the neck, threatening into shutting up.
In the end Frank and Joey grab pool sticks to make stakes while Sammy looks for garlic in the kitchen. Joey doesn’t help because she thinks killing Abigail would only make her dad mad at them. Once they’re ready, the trio rushes into Abigail’s room only to find it empty.
Suddenly they hear music so they go into another room, where they find Abigail dancing with Dean's body. At first she pretends to be a sweet girl, but when Sammy attacks, Abigail jumps on her and sniffs the garlic, which does nothing. Frank is pushed off when he tries to help but Peter manages to pick her up.
However Abigail easily throws him to the ground and takes the cross from his necklace, hitting his chest with it to make him bleed and confirming crosses don’t affect her either. Next Frank tries to stab her from behind, however Abigail quickly disarms him and stabs his leg instead. Giving up, the trio goes back downstairs, where Joey helps them with their wounds.
She reminds them that the injection did work when they kidnapped Abigail, and they still have a spare injection. They agree to split up and whoever finds the girl first must inform Joey through their earpieces so she can surprise her with the syringe. The group starts searching the house and Sammy takes a dirty corridor, where she’s startle by a bunch of bats.
This causes her to fall in a pool and she screams when she realizes it's filled with rotting bodies. Even worse, she has to crawl on them to get out. Meanwhile Abigail surprises Peter, who runs away in fear and locks the door behind him.
However Abigail breaks the door and keeps on chasing him as she runs with ballet moves. Peter’s running as fast as he can when suddenly Frank opens a door and hits him, causing him to fall off the rail. Then Abigail chases after Frank, pushing him down the stairs before sitting on him.
Joey uses the chance to try to inject her but Abigail hits her hand to send the syringe flying through a locked gate. Sammy grabs Abigail and pulls her away, so the child retaliates by biting her arm. Next, Abigail grabs Frank by the leg and starts flying, only for Peter to suddenly tackle her and make her drop Frank.
Peter holds Abigail down while Joey manages to retrieve the syringe, quickly injecting the sedative into Abigail. The child makes some serious threats and calls Joey awful things before passing out. Sammy freaks out and wonders if she’ll transform because of the bite.
Moments later, Abigail wakes up locked in an elevator. Joey says that if she reveals how to get out of there, they'll let her go. Instead Abigail confesses that she planned everything and that Lambert works for her.
She even knows all their real names and backstories: Sammy started her career by taking money from her rich parents' bank account and eventually went after a particular big fish. Peter served as muscle for a crime family and stole from his crew. Frank infiltrated a particular crime family while working as a detective and ended up enjoying the illegal life.
Joey is a former army medic who was fired for becoming addicted to medicine and she left her son with his bad father to become an underground doctor for some very shady people. One day she accidentally killed a gang member while trying to remove a bullet. It turns out everyone here wronged Lazaar or his gang in some way, and Joey says Abigail kills her dad’s enemies just to make him love her.
Abigail didn’t kill them as soon as they arrived because she likes playing with her food. She says that if they let her out, she’ll let two of them live. Frank suggests killing her, so an angry Abigail changes the offer to only saving the one that gets her out.
Peter quickly takes out his gun and Joey does the same as she and Frank explain Abigail is lying. Since Peter tries to free her anyway, Joey shoots him. Then the group leaves except for Frank, who volunteers to keep guard.
After everyone’s gone, Frank says that he’ll let her go if she tells him how to get out of the house. Abigail explains that he must pull Agatha Christie’s book in the library to open a secret door. Frank thanks her but refuses to release her, so Abigail easily breaks the door to push him and dances toward him.
At that moment Joey arrives and breaks wooden planks off a window, allowing the sunlight in. The light instantly burns off Abigail’s hand and she runs to hide in the shadows so she can regrow it while Joey and Frank run away. The entire group makes it to the library and stays under the sunlight entering through the high window Joey opened early.
Nothing happens to Sammy, so she’s relieved thinking she won’t turn. Frank pulls the book Abigail mentioned but nothing happens because she lied too. While he throws a tantrum, Joey tries to break down the wall to no avail.
She’s run out of candy so she’s getting very anxious. Joey explains to Sammy that she left her son to get clean and the plan was using this job’s money to go back to him and start over as a “reset”. Hearing this word gives Sammy an idea: if they can find the power source, she can short the locks.
The team splits in two and searches the house. Suddenly Abigail plays music again and takes control of Sammy thanks to the bite. She quickly transforms into a vampire and attacks Peter, biting his neck.
Abigail talks to him through Sammy while she continues to feed and kills him. Then Abigail has fun making Sammy dance like she does. Eventually Joey and Frank arrive, so Sammy keeps her face hidden.
However the others are suspicious, thus Sammy shows them her transformation and the duo immediately runs away. Sammy chases after them and they make it to the library, where Abigail uses Sammy’s voice to explains she hates that room because that’s where her father turned her. Joey grabs a tray and reflects the sunlight on it, causing Sammy’s body to explode.
At that moment a secret door opens and although Joey and Frank think it’s a trap, they decide to go through it anyway. After going through a corridor, they find the mansion's control and Lambert, who is a vampire too. Lambert grabs Joey by the neck while he explains everything.
Abigail turned him two years ago when she found out that he helped Frank infiltrate the gang. She also threatened his family, and now all he does is bring all her father's enemies here so she can play. He’s already notified Lazaar about the situation, and he’s on his way to the mansion.
Lambert wants to kill both Abigail and her dad, so he offers to turn Frank if he promises to help. Frank agrees, so Lambert knocks Joey out and bites Frank. Next Lambert makes Frank drink his blood and Joey wakes up to watch Frank painfully transform into a vampire.
Afterward Lambert tells Frank to feed on Joey, however Frank stabs him with a stake instead, causing Lambert to explode. At that moment Abigail arrives and tries to attack, but Frank overpowers her and drinks her blood. Joey uses the chance to reach the control panel and deactivates the security measures, she also retrieves her phone.
But when she runs down the secret corridor, the exit is locked. While Frank finishes feeding on Abigail and drops her body, Joey calls her son and leaves a heartfelt speech in his voicemail. Frank finds her and immediately pushes her back into the library, where he starts throwing her around to smash her against the furniture.
Joey tries to defend herself, but her punches do nothing to a vampire. Then she grabs her by the neck and throws her down, but Abigail catches her just in time. Abigail explains she's too weak to defeat him alone and begs Joey to help her kill Frank, promising to let her go if she does so she can see her son again.
Frank approaches them and the girls team up to start fighting him, but no matter how hard they try, he’s clearly stronger than both of them combined. After he knocks down Abigail, he stabs Joey in the shoulder with the stake and gets her stuck on a pillar. Then he goes back to fighting Abigail, biting her again as the girl raises her pinky to remind Joey of their promise.
One Abigail is down, Frank takes Joey off the stake and bites her neck before throwing her on the floor. When she wakes up, Frank uses his vampire powers to force her to pick up the stake and go after Abigail. However Joey is pretending, so she turns around and pushes Frank, giving Abigail the chance to jump on him.
She fights him again as she explains the powers take a while to develop fully so he can't control or transform Joey yet. While they’re distracted, Joey retrieves the stake and pulls Frank down, then she and Abigail team up to stab him and make him explode. Afterward Joey is worried that she may transform too, but Abigail confirms it won’t happen because Frank is dead.
As promised, Abigail lets Joey go and tells her to find her son. Suddenly someone grabs Joey’s shoulder: it’s Abigail’s father Lazaar, who says he had many names through the years. He wants to kill Joey, however Abigail comes to her defense, saying Joey saved her life and was there for her when he wasn’t.
Lazaar kisses Joey’s hand as thanks and lets her go. Joey rushes back to the van and discovers she still has a lollipop left, so she eats it while driving away.