When Hong Kong police inspector Lee Chung-chi (
Louis Koo) is informed about the sudden disappearance of his 16-year-old daughter Lee Wing-chi (Hanna Chan) during her trip to
Pattaya, he decides to travel to
Thailand to search for his daughter's whereabouts. There Lee receives assistance from local Chinese detective Chui Kit (
Wu Yue) and his Thai colleague Tak (
Tony Jaa) and also encounters American gangster Sacha (Chris Collins). Clues connect the disappearance of Lee's daughter to a case involving the mayoral candidate of
Pattaya's urgent need for a heart transplant. Lee also suspects the mayoral candidate's assistant Cheng Hon-sau (
Gordon Lam) of colluding with Sacha to abduct his daughter. While suffering from the loss of his beloved daughter, Lee kidnaps corrupt officer Ban (
Ken Lo) in order to get to the bottom of the case. As a result, Lee becomes a nationwide wanted criminal. Seeking revenge, Lee can only ask Chui to assist him in finding the whereabouts of his daughter. In an attempt to gather evidence to locate Lee's daughter, Chui and Tak arrive at an apartment owned by a Taxi driver who has dashcam video of Lee's daughter but Sacha and his gang reach him first. Chui and Tak get into a fight with Sacha and his gang. Chui subdues Sacha's men while Tak pursues and fights Sacha. Although Tak dominates and wins the fight by kicking Sacha off a building rooftop, Tak saves Sacha from falling and attempts to arrest him, but Sacha feigns defeat then throws a bystander child off the building. Tak saves the child, but is kicked off the building by Sacha, resulting in Tak's death. Under interrogation, Ban reveals the location where Lee's daughter is stored. On his way there, Lee's car collides with Cheng's car, which is carrying his daughter. Police pursue Lee after spotting a bloody Ban. Lee leaves Ban behind and barely escapes, while his daughter is brought to Sacha's headquarters by Cheng. Ban is then killed in the hospital. Police commissioner Chai (
Vithaya Pansringarm), who is aware of the plot to save the mayoral candidate, tells Chui to drop the case, warning that a cover-up is already happening and that their own lives are already at risk. With the heart transplant operation complete, Cheng orders Chai to have the police kill Sacha and his henchmen. Before the police enter, Lee rushes into Sacha's headquarters, defeating many of his henchmen, but is injured due to being overwhelmed. Chai mandates that the police operation should continue so that Lee is killed as well. Angered at this, Chui punches Chai, enters to save Lee, and continues the battle against Sacha and his henchmen. Chui managed to kill and injure Sacha's remaining men and engages in a brutal fight with Sacha. At Chai's order, the police SWAT team, storm Sacha's headquarters, killing the remainder of Sacha's henchmen, forcing Lee, Chui and Sacha to hide. Chui reveals the awful truth to Lee, who goes on to find his daughter's corpse and grieve. Chui manages to almost defeat Sacha, but Sacha uses a fire extinguisher to knock out Chui and attempts to kill him with a bonesaw, but a raging Lee interrupts. Locked in a struggle, Lee savagely bites Sacha's ear and fatally slashes Sacha's throat with the bonesaw. Chai arrives and nearly executes Lee, but stops at Chui's urging at Chai reminding him that they are still cops. Chai then shows Chui that Chui's wife has been kidnapped at the behest of Cheng. Lee volunteers to save Chui's wife. Chui drops him off at the mayoral candidate's residence, during the birthday celebration of the mayoral candidate's granddaughter. Lee handcuffs Chui to the steering wheel of his vehicle to avoid interference and breaks into the sleeping mayoral candidate's room and listens to his daughter's heart. Cheng appears and tells Lee that he, not the mayoral candidate, is the one behind the crimes. Lee asks if Chui and his wife will be left alone with his own death, Cheng agrees. Lee kills Cheng and spares the mayoral candidate. Having lost his wife and daughter and driven over the edge, Lee turns the gun on himself and Chui hears the sound of a gunshot outside. Chui's wife is released; she eventually gives birth. Chui is initially elated at the childbirth, but his happiness fades as he remembers Lee's sacrifice for him. ==Cast==