Special Agent Zack Grant's (RUSSELL CROWE) wife died seven years ago giving birth to their son Eric. Grant never recovered from the shock nor dealt with his grief, and his work has suffered - consistently and repeatedly. The FBI sting operation he is now in charge of is his chance to redeem himself and it may be his last chance. Grant's career is on the line. If he doesn't succeed in this mission there is no way back.
He has carefully trained new agent Saiko, a young Japanese-American woman, to infiltrate the Italian mafia. Saiko is to enter mob kingpin Victor Serlano's penthouse disguised as a high priced call-girl and plant a transmitter in his home. But Saiko has her own agenda. Once inside the penthouse she flushes the transmitter down the toilet. When Zack hears the transmitter go dead, he immediately senses his plan has somehow been thwarted. Expertly trained in martial arts, Saiko quickly manages to disarm and disable Serlano's henchmen and then kills Serlano. As Zack rushes into the room, Saiko throws herself out the terrace window, plunging to her death. Zack, again, has failed.
At the same time, Frank Serlano (MICHAEL LEANER) is claiming the remains of his only son, Victor, from the coroner's office, Grant is slowly begining to put the pieces of the puzzle together: he soon discovers a link between Saiko and Tetsuro, the head henchman for the Yakuza. Yuji Koyabashi (ETSUSHI TOYOKAWA) runs the Yakuza in America and Tetsuro is in America to help the Koyabashi family settle into this country. Determined to succeed in his temporarily aborted mission, Zack enlists the aid of another undercover FBI agent to implement a new plan. Together they manage to infiltrate the Koyabashi headquarters by posing as businessmen and are introduced to Yuji and Tetsuro. All moves smoothly and according to plan until Saiko's name is mentioned. Suddenly there is a discernible tension in the room.
At Yuji's command the Yakuza break into gunfire just as Serlano's men arrive to capture Yuji. Zack thrusts a gun against Yuji's temple and they back out through an open doorway and flee. As Zack heads towards the FBI office with Yuji he gets a phone call - Serlano, who has kidnapped Grant's young son, Eric. Serlano wants to swap hostages, Eric for Yuji, who he believes is responsible for his son's death. Knowing he has no choice, Zack follows Serlano's directions and boards a plane with a handcuffed Yuji. But Serlano has added his own safeguard: He's placed one of his henchmen, Viggo, on the plane.
Yuji tries to proclaim his innocence in Victor Serlano's death, but Zack won't listen. Exhausted, both men fall asleep, only to be abruptly awakened by Viggo, who congratulates Zack on capturing his hostage for the Mafia. Yuji is now aware of Zack's betrayal. Later in the flight, when Zack accompanies Yuji to the bathroom at the back of the plane, Viggo notices their seats are empty and makes his way to the back of the plane. He finds Zack standing outside the bathroom. Yuji has fashioned a pointed shaft out of the toilet paper roll: He lunges out of the bathroom, spears Viggo in the leg, and makes a dash towards the cockpit. Zack struggles to regain his balance and stumbles after him. Suddenly Yuji appears from around a corner with his own hostage - Mary (HELEN SLATER), the giddy flight attendant.
With Mary in front of him, Yuji makes his way into the cockpit and forces the pilot to crash land in the middle of a field in Arizona. Yuji escapes and hijacks a car from one of the locals who's driven by to see the wreckage. As Zack commandeers a car from another of the local residents, he spots Mary running towards him and orders her to stay put. After crashing both cars, Zack wrestles Yuji to the ground. Once again hostage, Yuji denies his role in the deaths of Victor and Saiko. Zack is beginning to feel guilty about leading Yuji to certain death at the hands of the mafia; he needs Yuji to confess to clear his conscience. But Yuji stands fast and Zack has to back down. He is beginning to understand the Japanese code of honor and justice.
Viggo and the rest of the hoods arrive - and they have Mary. But FBI agents, alerted by the local police, also appear and demand the release of Zack and Yuji. When Zack refuses to hand over Yuji to the FBI agents, they are stunned. His betrayal has caused a standoff. Suddenly a chopper flies into view: it's Tetsuro, arriving to rescue Yuji. Pandemonium erupts as gunfire and shouts turn the standoffinto a bloody three way shooting gallery.
Zack and Mary escape with Yuji in tow in one of the Fed's vehicles. Zack calls Serlano and they agree to conduct their trade at Griffith Lake the following day. As they head out of Arizona, Yuji explains Saiko's actions: A previous mafia massacre took the life of Saiko's godfather, the man who had provided a home for her and her family. Saiko's act was personal, one of revenge. As Zack begins to understand Yuji's explanation his guilt resurfaces: he feels tormented about turning Yuji over to the mafia, but still feels he has no choice.
Suddenly a police car pulls them over - for speeding! The trio decides to play it cool. As the officer reports in, Viggo picks up the report on his scanner. The FBI has requested Zack's arrest, and now he and Mary are in the back of the police car while Yuji is handcuffed in front. They are followed by Viggo's men, and within moments the policeman is shot dead, causing the car to spin out of control and crash. Miraculously, Zack, Mary and Yuji are not killed. As Viggo approaches the wreckage Yuji manages to free himself, killing Viggo with the policeman's gun in the nick of time.
A free man, Yuji begins to walk away from the car, leaving Zack and Mary locked in the back seat. He ignores their pleas for help until Zack appealing to Yuji's code of honor, apologizes for his accusations and for misleading him. Yuji returns and confesses that Saiko was his sister and that he did ask her to kill Victor. In his desire to see his family avenged, he never thought Saiko would kill herself. As Yuji frees Zack and Mary from the wreckage, the men reach an understanding.
The following day, Serlano and Zack's son Eric are on a boat in Griffith Lake with Serlano's thugs surrounding them. As Zack calls out to his son, the sound of a car horn breaks the silence: It's Mary, creating a diversion. As Yuji kills several of Serlano's men, Zack attempts to rescue Eric. Yuji is shot and falls overboard. As he drags himself out of the murky waters, Serlano spots him. Yuji pulls himself up and fires a direct hit, but as Serlano drops over the side of the boat he grabs Eric and takes the child down with him. Zack frantically dives in the lake and finally locates Eric. As they makes their way over to Mary and Yuji, all breathe a sigh of relie_ Another war has ended. For now.