THE PLOT:Decorated and highly-skilled CIA Special Activities Division officer Bryan Mills (Liam Neeson) has recently retired. Although his frequent absences led to his divorce, he remained a loving, albeit distant father to his teen-aged daughter, Kim (Maggie Grace). Hoping to bond with Kim, an aspiring singer, Bryan buys an expensive karaoke machine for her 17th birthday. But his gift is upstaged by Kim's wealthy stepfather, Stuart (Xander Berkeley), who gives her a horse at her party.
Later, Bryan's former CIA colleague, Sam (Leland Orser), hires Bryan for a one-night job with him: bodyguards for a famous singer, Sheerah (Holly Valance). After fending off an armed attacker, Bryan earns Sheerah's gratitude and a promise to help with Kim's musical aspirations. Kim invites Bryan to lunch the next day, but before he can share his good news, he discovers his ex-wife, Lenore (Famke Janssen), is also there; the lunch is actually a set-up to persuade Bryan to sign a parental consent form allowing Kim to travel to Paris with her 19-year-old friend, Amanda (Katie Cassidy), who is visiting relatives there. Lenore is irritated when Bryan refuses to sign, and Kim, upset, tearfully rushes out. Wanting to win back his daughter's favor, Bryan reluctantly agrees to give his consent, but he is angered when he discovers later the girls are actually following a U2 concert tour throughout Europe. Affronted by Lenore's denial of the dangers, he is pressured by Lenore into letting Kim go.
In Paris, Kim and Amanda meet an attractive stranger named Peter (Nicolas Giraud), who suggests sharing a taxi, and also invites them to a party. But events soon turn sinister when, after Kim and Amanda are dropped off, Peter calls someone on his cell phone, giving them the apartment's address and information about the girls. Kim, meanwhile, learns that Amanda lied—they are actually staying at the apartment alone—a fact that Amanda revealed to Peter.
While talking to Bryan on her cell phone, Kim witnesses Amanda being abducted in another room. Bryan warns that she will be taken as well, and instructs her to shout out information about the kidnappers as he tapes the call. Kim then screams frantically while Bryan hears it all. Bryan realizes that the kidnapper had picked the phone up. Bryan then tells them that if they let her daughter go he will not chase them down, but if they refuse, he replies that he will "look for you [the kidnapper], I will find you, and I will kill you." He receives an answer of "Good luck!". Sam analyzes the recording and determines the kidnappers are the Albanian Mafia operating in Paris, who largely deal in sex slaves (Human trafficking). On average, these kidnapped girls have 96 hours (four days) before never being found.
At the Paris-Charles de Gaulle Airport, Bryan locates Peter as he lures another victim into a taxi. Attempting to escape, Peter is hit and killed by a truck. Bryan contacts an old friend, Jean-Claude (Olivier Rabourdin), who works for French Intelligence. Though doubtful that Kim can be found, he provides information on where Albanian pimps and their prostitutes operate. Navigating his way through Paris seedy underbelly, Bryan goes to a construction site where he finds groups of girls being drugged by the gang members. He notices one of them has Kim's jacket (to which she wore when leaving Los Angeles). He and the girl are pursued through the construction site but manage to escape to a hotel where Bryan nurses the girl back to life. She tells him of a house where Kim might be. He bluffs his way in, and, identifying a gang member's voice from the phone recording, kills nearly everyone there. Amanda is found dead from an apparent overdose, but Kim is already gone.
Mindful of the 96-hour deadline, Bryan tortures the surviving gang member, Marko, by hooking him up to wires and electrocuting him into revealing that Kim was sold to Patrice Saint-Clair (Gérard Watkins). Bryan then leaves Marko to die. Bryan returns to Jean-Claude's apartment and, deducing his connection with the human traffickers, confronts him about his illegal Albanian dealings, threatens to kill Jean Claude and shoots his wife in the arm to obtain Saint-Clair's address.
At Saint-Clair's, Bryan poses as a police commissioner in order to gain access to a party of French elites. Bryan eventually finds his way to a secret elevator and after killing the guard, enters the secret underground where the sex-slave auction takes place. After taking out a few guards, Bryan enters a darkened auction room posed as a champagne server. His daughter, Kim, is the last girl to be auctioned off, and after holding a gun to a buyer's head, Bryan forces the man to purchase Kim. Before Bryan can rescue her, he is knocked unconscious by surprise. Bryan is handcuffed to pipes outside of the auction room in front of numerous armed guards (Bryan takes notice of the man in possession of the keys to the handcuffs. Saint-Clair orders Bryan to die a quiet death as to not disturb the party upstairs. Bryan finds the keys to the handcuffs from a dead guard, killing Saint-Clair's henchmen, then forces Saint-Clair to reveal Kim's whereabouts before killing him. After finding the whereabouts of his daughter, Bryan attempts to run after an Audi (which he notices is Qatar registered) leaving the party en route to the yacht where Kim will be shipped on. Bryan runs after the car and eventually is able to steal the car once it is parked. He chases down the yacht by driving the wrong way on the highway in order to get to a nearby bridge where the yacht will pass by. Bryan boards the yacht by jumping off the bridge onto the yacht belonging to the fat prince who bought Kim, killing his guards in the process. After disposing of all the guards, Bryan enters the room where the fat prince holds a knife to Kim's neck and tries negotiating with Bryan, but Bryan shoots him dead. A short reunion scene is followed by Bryan and Kim returning to the United States, and, shortly thereafter, Bryan surprises Kim with a visit to Sheerah's house to help Kim launch a singing career.
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