Seven tourists with troubled pasts find themselves trapped at a satanic mill in rural Holland. As they're attacked for their sins one by one, the night becomes a fight for survival.
Jennifer is an Australian girl on the run from her past who washes up in Amsterdam. In a desperate attempt to stay one step ahead of the authorities, she joins a coach-load of tourists embarking on a tour of Holland's world famous windmills. When the bus breaks down in the middle of nowhere, she and the other tourists are forced to seek shelter in a disused shed beside a sinister windmill where, legend has it, a Devil-worshiping miller once ground the bones of locals instead of grain. As members of the group start to disappear, Jennifer learns that they all have something in common - a shared secret that seems to mark them all for doom.—Nick Jongerius
Amsterdam, Present Day - Mr. de Vries discovers his Australian nanny Julie is actually fugitive Jennifer Harris. Jennifer hits him with a vase and escapes.
Jennifer ends up hiding on a countryside tour bus with young boy Curt and his distracted businessman father Douglas West, drug-addicted doctor Nicholas Cooper, former model and aspiring French photographer Ruby Rousseau, hungover soldier Jackson, and Japanese tourist Takashi Kido, who is in Holland to honor his late grandmother. Abe drives the bus.
Thinking she sees her dead father in the road, Jennifer forces Abe to suddenly stop. The bus becomes stalled. Jennifer and Jackson go on foot to look for help at a nearby windmill.
In the forest, Jackson has a flashback to murdering a prostitute while in a sudden rage the night before. A supernatural stalker with a scythe appears, cutting off Jackson's legs and stomping on his head.
Jennifer runs back to the others. After hearing her wild claims of what happened to Jackson, Nicholas diagnoses Jennifer as delusional. Something suddenly hits the bus. Everyone runs out just before the bus overturns into a stream.
Curt cuts himself in the escape, which worries his father since Curt is a hemophiliac. Everyone sets out to see if there is a miller at the nearby windmill who can help them. Takashi goes off on his own when he follows a vision of his family dog.
The group stops at an abandoned shack to care for Curt while Abe goes alone to the windmill. Abe comes back claiming that the windmill's doors were closed and no one was there.
Takashi follows the dog to a clearing where he sees an empty rocking chair. Takashi becomes haunted by memories of euthanizing his grandmother, but expresses regret for his actions. The Miller appears and raises his scythe.
Abe finds a parchment in the shack that is a centuries-old death warrant for a local miller named Hendrik. Townspeople killed Hendrik and burnt down his mill for practicing witchcraft and allegedly making a deal with the Devil. Nicholas fills in other details about the Miller Hendrik legend.
Outside, Nicholas is drawn away by the sight of an operating table between the trees. Nicholas sees a patient on the table who died when he performed surgery while on drugs. Nicholas shouts that he isn't to blame for her death. The Miller appears and disembowels Nicholas.
Takashi returns to the others. With Ruby translating, Takashi explains that he believes they are all standing at a gateway to Hell to be punished for individual sins. Takashi survived the demon's wrath because he expressed remorse for his actions. Without repentance, they are all bound for damnation.
Abe recounts a part of local legend that says the Devil was so pleased with the miller that Hendrik became a gatekeeper for Hell after his death. Meanwhile, the Miller drains the blood from Nicholas' body and uses it to power the windmill.
Jennifer relives killing her abusive dad by setting his trailer on fire in order to protect her little brother Danny. Unknowingly, Danny went back inside the burning trailer to retrieve a koala toy and he died too.
Ruby openly confesses to arranging for Yakuza to cut a rival model who later committed suicide. Ruby is drawn to her reflection in a puddle outside and is forcibly drowned.
Douglas and Abe go to the mill when they see it working. They find bodies strung up inside and realize Jennifer and Takashi were telling the truth. Remembering his son, Douglas races with Abe back to the others.
Jennifer and Takashi conclude that they need to burn down the windmill to close the gateway.
Curt discovers that his father's sin is that Douglas strangled the boy's mother. Curt runs away. Douglas goes after him, but the Miller strangles and decapitates Douglas with a rope.
Takashi suggests to Abe that they get gas from the bus to start the fire at the mill. Abe suddenly stabs and kills Takashi while Jennifer is elsewhere with Curt.
Jennifer retrieves the gas and goes to the mill with Abe and Curt. There she discovers that Abe is the Miller's servant. The Miller drags Jennifer outside while Abe prepares to kill Curt since he is an innocent boy that the Miller cannot harm.
Jennifer attacks a vision of her father and beats him to death with a bone. The Miller prepares to kill her. However, Curt gets away from Abe and uses a lighter to ignite the gasoline inside the mill. Outside, the Miller suddenly starts burning and explodes.
Jennifer rushes inside and stops Abe from strangling Curt by slashing Abe's throat. Jennifer and Curt escape as the burning windmill begins crashing around Abe.
Thinking they made it to safety outside, Jennifer and Curt are surprised to see the Miller standing in the windmill's flames. The Miller hooks Jennifer by throwing a chain into her face and drags her back inside the mill as it is destroyed. Curt survives.
In the light of day, Abe drives his tour bus on the road near the windmill as it starts reappearing in the background. Abe returns to town and picks up a new busload of sinners.
