The Japanese ambassaor is visiting Marseilles to view the city police's anti-gang tactics. During the visit, however, he is kidnapped by a group working for the Japanese yakuza. Young officer Emilien is determined to rescue the ambassador and officer Petra (his girlfriend), who was also kidnapped, and restore the honor of his department. Once again, speed demon taxi-driver Daniel (from the first Taxi movie) is called upon to save the day with his high-speed driving skills.

In France in the darkest days of the Great War Camille receives an alarming letter from her soldier boyfriend. Disguising herself as a man she sets off to try and find him. As she lives near the Western Fromt she hooks up with a passing group of French soldiers without too much trouble. But there's something a bit odd about these stragglers, and it's not just their habit of bursting into song at every opportunity.

The Andorran hooker and single mother Catalina "Cat" Rona is hired to participate in an orgy in Montenegro with other escorts and powerful men and the American Senator William Krebb. Something goes wrong with the politician and all the girls are murdered by the security of the host to avoid witnesses. However Cat escapes and brings a hard-drive with classified information with her. There is a manhunt for Cat and the cruel assassin Helen Bingham is hired to retrieve the HD and kill Cat. Meanwhile the Americans Julian Simms and Anthony Hester decide to open a detective agency to raise money. When they see on the newspaper that Cat is being chased, they decide to seek her out expecting to receive a reward. However, they cross the path of Helen and they end protecting Cat from the killer. When Helen is betrayed by those who had hired her, she decides to help Anthony, Julian and Cat to retrieve the HD and their freedom.