The film opens with a real estate tycoon Wong Ho-chiu celebrating his wife Mrs. Wong and his adult daughter Daisy on her birthday. Daisy longs to travel overseas, in particular to see the Salar de Uyuni in Bolivia, but a heated argument with her father sends her racing out of the house. The next day, Wong receives a cellphone video message showing Daisy has been abducted, with her captors demanding ten million for her release. He refuses to involve the police, convinced it’s Daisy pulling a dangerous stunt for money, and warns the kidnappers that if anything happens to her, he will stop at nothing to avenge her.
Because of this vow, the kidnappers grow more agitated and decide to kill Daisy, leaving her bound, gagged and blindfolded, with a plastic bag over her head to suffocate her. Wong then enlists his most trusted bodyguard, Chor, to locate her. As Chor traces her whereabouts, the tension tightens, and the search climaxes in the devastating discovery of Daisy’s body.
When the news reaches Wong, he is crushed to learn that his daughter is dead. He fabricates a story, telling everyone that Daisy is alive and has been sent to L.A. He pushes Chor to the front lines of revenge, going so far as to have Chor videotape each of the executions. Each time a new tape arrives, Wong prays, seeking some measure of solace or justification for what he’s doing.
As the pursuit continues, the third perpetrator is tracked down, and Wong’s wife finds out about the relentless killings. She pleads with him to stop, but he refuses, which leads to her decision to leave him. The spiral intensifies when a medical check-up reveals that his assistant came to pick up Daisy’s heart-ailment medicine, prompting Wong to confront the circle of people involved and to realize who the final perpetrator is.
The final perpetrator is revealed to be Daisy’s female assistant. During a tense confrontation on a rooftop, the assailant fights back and falls off, only to reveal that she has a daughter. Witnessing the daughter triggers a torrent of memories of Daisy’s childhood in Wong, slowing his hand and giving him pause about killing the assistant. They manage to pull the assistant to safety, and the two of them disengage from the deadly pursuit.
Chor offers to take responsibility for everything, but Wong insists the burden isn’t his to bear and declines to drag Chor further into the nightmare. The two men part ways, each carrying the weight of their choices but choosing to walk separate paths from that point on. With the quest for vengeance behind him, Wong travels to the Salar de Uyuni in Bolivia with Daisy’s ashes, spreads them across the salt flats, and finally breaks down in tears, haunted but moved by the memory of his daughter.
