A man is in a room full of tools and posters that show the way he wants to dismember certain people. He is dancing the whole time while he is seeing pictures of the victims-the ones in the posters-that will assist to a company retreat, the company's name is MASTUR Bait, and it is specialized in selling bait. The man puts all the pictures in an envelope, and reveals his real objective: to become the best serial killer in the world. The first thing he does while still in the room is to choose a name: he comes up with the Boner, and then he laughs a crazy laugh while the movie fades to the cabin where the retreat is going to take place.A car arrives with Carl, the first to arrive. It is revealed then that the retreat will take a week. While he is checking what it seems to be a bachelor party with all females, the Boner appears and takes him to a room. He can not move or speak, but the Boner tells him not to worry because he is going to die very soon. Seconds later, he takes what it seems to be a Carl's rib and stabs him until he dies. He then takes an analog counter and click it until it shows 1. Moments after that, it is Kev and Mike who arrive to the cabin. While they are on the inside, three girls arrive. One of them is Kev's girlfriend, Katie, and as a joke when the girls enter the room, Kev is faking a fellatio with a dildo to Mike. Kev's girlfriend gets very upset and leaves the room while the other two girls make funny comments, for example talking about his technique or the fact that his girlfriend thinks that he may be gay, to what he reacts very surprised. Then Kev leaves the room, and he goes to look for her.While the others are inside talking, Kev overhears a conversation of his girlfriend talking with his mother about the fact that Kev may be gay. While talking to her mother, it is implied that Kev made her to put her finger on his rectum-although she entered the whole fist-and that is why she thinks he may be gay. Kev arrives to the balcony where her girlfriend is, and he starts screaming that he is not gay. At the same time, both Red-the new IT guy-and Doug-the boss-arrive to the cabin in a car. And two new girls, Jessica y Brenda-co-workers and best friends-, arrive too. Doug introduces Red to Brenda and Jessica. Then, Jen appears screaming from the balcony of the cabin that Carl's car is there, but there is no trace of him. At this moment, everyone enters the cabin. While everyone is entering the cabin, Kev is still speaking to his girlfriend, who still thinks he may be gay because of a picture of Warren Beatty he keeps in his bedroom. He tells her that him and Ishtar are his favorite actor and movie, respectively.While Red is putting the groceries in the fridge he sees Katie and Kev outside, but Jessica tells him that it is allowed because they were dating before both entered the business, so if anything happened between her and Red they have to be quiet about it. After telling her that if she is joking, he will kill her, Doug and Red go outside to explore the property around the cabin. They arrive to a tool shed with a sing of private on the outside. Doug thinks the family that owns the cabin is staying there, while Red smells of blood. It is assumed that the tool shed is where the Boner has settled his safe house. At that moment, Jen is still trying to contact Carl like she describes it screaming to the couple near the tool shed.That night, while Mike is preparing the barbecue outside, Jen and Doug are unpacking. A hand takes all the meat Mike left outside and changes them for what it is supposed to be Carl's meat. At a given point, inside a room in the cabin where they are alone, Jen slaps Doug on the face, which gets him very angry. He punches her so strong that she goes against a piece of furniture. She, then, takes a chair of wood and smashes it against Doug back. He falls down and when he gets up he starts strangling Jen, but then he tears apart her blouse, exposing her breasts. She does the same with Doug's shirt, and they start to kissing each other. Mike presents to everyone, except for the two previous characters, the meat, and they start eating while the Boner is seeing everything from outside the window. They are eating, and they find an earring that belongs to Carl, and everyone looks surprised at Red as he is chewing the bones-but not because they suspect something about the meat-.Doug and Jen arrives to the eating room as the others have finished eating. Mike assumed that they had sex, and he makes coarse metaphors about the fact; as in banana or to make a download. It is clear from the conversation that there is some kind of friction between Jen and Jessica. Jen goes to the bathroom, and she cuts herself with a cutter to relieve some tension. Meanwhile, Mike and Liana are in the kitchen. She offers to go to a room together while they are kissing, but Mike sees the bachelor party from the window and without Liana noticing, he leaves the kitchen to search for Kev and go to the party. Just before that, Kev is seeing pictures of Warren Beatty on his laptop. When Katie arrives, he acts as if he is working on something, and again they have a conversation about Kev being gay. When she leaves the room upset, Kev watches what it seems to be a picture with 1979 on the back. In the kitchen, Liana is talking with Sara, and then they kiss each other. On the way to the party, Mike and Kevin encounter Red, and he decides to go to the party too.They finally arrive to the party and a woman lets them in. Seconds after they start to partying as crazy people with the girls, sniffing coke, drinking a lot, dancing, etc. At a given point, even Mike and Kev start to kiss each other. All the while the Boner is planning to kill Liana and Sara, but instead he draws a penis on the face of Liana, and he puts some shave cream on the hand of Sara, and he tickles her face. Then he goes to the party, and he puts some substance on the drinks without the people there noticing. After drinking, everyone is falling asleep, and then the Boner clicks the counter in the tool shed until it shows 7.The next day, Liana and Sara wake up, and they realize what the Boner did to them. They think is Mike, though. Liana thinks that if Mike saw them last night, he would be heartbroken. Then it is Mike who wakes up, he is in the party and when he tries to withdraw his hand from the body of one of the girls he pulls an organ, and he realizes she is dead. He throws the organ to Kev, waking him up, and then the latter throws it to Red, waking him up as well. When this one tries to move away his hand from a girl breast, he realizes that he has his hand glued to her breast. He ends pulling off her breast as Mike and Kev notice that all the girls in the party are dead. At this point, Kev complaints about pain in his testicles. The trio run away from the cabin, they stop to discuss the situation and Kev is still complaining about the pain. Then, Kev realizes that the pain in his testicles is due to what the Boner did to him: he put his phone inside his testicle scrotum. The Boner is watching and laughing all the while, and contemplating Red's poster, he announces that he wants to kill him next. At that precise moment, Mike accuses Red of being the killer and Mike hits him with a pointing branch on the face, and then he sticks it on his chest. They hear Bone saying "no"-Red was his next victim-but then he fakes a golf play, and they believe it.They-Mike and Kev-decide to go to the cabin and come later to find Red. At that precise moment, Katie calls Kev to the cellphone, and he complains again about the pain. Seconds later, the Boner is taking down Red's poster in the tool shed. He speaks to a rifle with a sing of "for emergency use only". Meanwhile, Jen and Doug are preparing a presentation for the team and Jessica and Brenda are talking in the kitchen. Mike and Kev arrive to the cabin, and they encounter in the waiting room Kev's girlfriend, Sara and Liana. They talk about the last night, what Mike "did", when they are asked what they did last night Mike says they slept under the stars and Liana thinks it sounds gay. When everyone leaves, Kev insists in loving Katie and not being gay. Mike tells him why not tell to everyone and Kev answers him that they would not understand what he has to say.They are now in the presentation with Doug asking for Red. At the moment he asks if anyone has seen him, Mike sees him though the window dragging himself with the help of the breast glued to his hand, Kev sees him as well. Then Mike says he has to go to the bathroom, not before covering the window with the screen glare. At the same moment, the Boner is putting the poster of Red in the wall again. Mike goes out through the bathroom window, but he hits himself with a board with some claws on his forehead, making believe the others that his scream was in fact a golfer-as previously the Boner did-. Mike takes Red to the woods again and leaves him there and promises him to get back to him when all is over. The Boner, visibly upset, takes the poster again from the wall, this time tearing it. Mike then comes back to the reunion and the night comes.While Mike and Kev are on the outside planning what to say about the night they spend on the party, Katie calls Kev. He is hurting, so Mike tries to make the phone stops. Katie sees everything from the window and from the way she sees them it seems that Mike is masturbating Kev. Meanwhile, the Boner decides to kill both Doug and Kev. Jen and Doug are discussing firing Jessica, and Mike is trying to get out the cellphone from Kev's testicles. Then Katie finds a picture of Warren Beatty inside Kev's wallet, and she gets upset and calls him a liar. The phone is finally outside Kev's scrotum, and he makes Mike promise that if anything happens to him, he will find his father-Kev's-and tell him he loves him.Later that night almost everyone is in the waiting room, Mike and Liana are kissing each other while Sara is visibly upset watching them. When Liana accuses Sara of being jealous, they end kissing each other in front of everyone while the Boner is seeing everything from outside. They talk again about Red's disappearance, and Katie enters the bathroom, visibly sad. She plugs the hairdryer and gets in the tub, the rest are playing cards in the waiting room, and Kev enters the bathroom as well. They have a discussion again about him being gay, and things escalate when Katie tells Kev that she knows his secret. In the meantime, Jen and Doug are doing again their sex routine. In the bathroom, Kev promises Katie that it does not look what it seems. She accuses him to love Warren Beatty and when he confesses it is true, and he is about to say why, Katie throws, in rage, the hairdryer into the tub causing Kev's dead by electrocution. Seconds after, Jen, without noticing because of the sex arousal, introduces to Doug a cutter in his throat, killing him as well. Katie and Jen panic and decide to hide the facts, they both take a towel from a wardrobe, and they start to hide the bodies, throwing them out of the window at the same time. Meanwhile, Mike and Liana are kissing in the kitchen, but Mike goes out with Jessica to look for some games in the car, then Sara arrives, she kisses Liana and leaves. Seconds after, Brenda arrives, and she also kisses Liana on the neck asking her when they can be together while Sara is watching everything from the distance visibly upset. Before Mike enters the room, they both agree to meet with each other at 3 a.m. in the car.On the outside, Jen and Katie encounter each other while they are on their way to get rid of the bodies. All the time, the Boner is watching everything. When they start to say sorry to the bodies, they uncover the bodies and, unknowingly, they changed bodies, so Jen has Kev and Katie has Doug, and they think they are going insane. The Boner starts to being frustrated, and he compares them to cock blockers for serial killers, and he complains that there is no fun anymore. He goes to the shed tool, and he takes down Kev and Doug posters. Later, Brenda leaves the house to meet in the car with Liana and the Boner has his hopes up again, speaking to himself very excited. Then suddenly, Sara appears, and she locks Brenda in the car, and she connects a plastic tube from the escape to a window slightly open. She argues with Sara about protecting what hers. Then, the Boner curses, and he has to fake again being a golfer. When Sara leaves the place, the Boner tries to revive Brenda in order to kill her. He achieves it, only to put some chloroform on her and take her to the tool shed. When she wakes up, the Boner has removed both of her legs, and he announces to her that he is going to hammer what it seems to be a pointing femur into her heart and then kills her.At the same time, Red is trying to drag himself to the cabin again-still with the breast-and having visions of him and Jessica kissing or playing with children. The next day, Jen and Katie are alone in the waiting room and the first tell the second that the dryer does not work. She acts as she knew nothing, and then tells Jessica that she has not seen Kev since last night; Jen says the same about Doug. They both agree to each other that Kev went to look for Red, and then Doug went to look for Kev. Then everyone arrives with breakfast, and they start to try to guess where is everybody-the dead people-. At a given point Mike sees again Red through the window dragging himself. Mike then arrive with a wheelbarrow, and he takes him again to the woods. In the meantime, Liana goes outside with the pretext of looking for Red, then the Boner arrives. He puts her to sleep, when she wakes up in the tool shed, the Boner tells her that she is there for her own protection due to almost everyone killing someone.Mike arrives to the cabin again, and he starts getting upset because the others are not there. Everyone goes out, except for Jessica, to look for the others. After 30 seconds they go inside again because there is no point in looking for them-but never recognizing it to each other-. When Jessica comments that they passed less than 30 seconds looking for them. Katie feeling guilty confesses having killed Kev because she found a picture of Warren Beatty in his wallet, and it was a proof that he was gay, but then Mike tells her that Warren was Kev's dad. After Katie confesses, everyone starts to confess their crimes, so now everyone knows that Brenda, Kev, and Doug are dead and Red is almost dead. Jessica decides that she is going to tell everything to the police, but the rest threaten her to kill her if she says anything. Then, everyone agrees to get some rest.Next, Sara is in the kitchen cooking, Jessica is in the porch contemplating a picture of Brenda and herself-they were best friends-. Katie is sitting and smelling a Kev's t-shirt, Jen is chopping wood. Mike is playing in the swings. At a given point Jessica comes to the kitchen and starts eating with Sara, while eating her cupcakes, suddenly Jessica takes a knife and stab Sara in the back for Brenda. Mike is playing with a stone, and suddenly he gets up from the floor and approaches Jessica, seconds later he takes Katie outside and tells her to throw stones on the other side of the house. Then Mike enters the kitchen where is Jessica washing her hands, and he tells her the same, to throw rocks to the other side. She throws one, and they hear a scream, while the Boner is watching everything, they both see Jen dead on the floor. He tries to blame her but according to Jessica it was him who kill her, but now if she calls the cops she has as much to lose as them. Then she confesses to have killed Sara, the Boner complaints again and takes Jen and Sara's poster from the wall. He puts some gloves, takes a hammer, and he finally takes the rifle "for emergency use only".Both Jessica and Mike tell Katie about Sara and Jen outside the cabin, and the Boner puts to sleep Jessica and Katie with the rifle. Mike runs away while the Boner follows him but then by accident the Boner hits himself with the rifle, although he finally gets Mike, but he is now unconscious. When the Boner wakes up and at night, he takes everyone to the shed tool. Mikes wakes up first tied up to a table and the Boner shows him the head of Liana. Katie is already dead also in a table. The Boner tells Mike that he blames him for ruining everything, and he cuts his finger. He then cuts his hand and put it in Mike's mouth while he stabs him with Katie's bone.Red arrives from behind at that precise moment and hits him with the breast, the Boner falls down, and he hits him until he is apparently dead. They discuss the fact that Mike abandoned him. The screen goes to black and next Mike has an axe in his forehead. Then Red starts clicking the analog counter until it shows 11. Jessica and him leave the shed tool and Red tells her that they can go together and live on a boat. Jessica answers him that she does not feel that way about him and in rage Red pushes her against a tree with a pointing branch, so she dies too. Before the tittle of the movie appears the breast finally falls down and after the title Red stumbles and falls. Without knowing if he is alive or dead, the movie ends.