After another failed infiltration of the Eastern European underground group Anarchy 99, National Security Agent Augustus Gibbons seeks a new type of agent. Extreme sports fanatic Xander 'xXx' Cage, is infamous for his wild and often illegal behavior. After his latest run-in with the law, crashing a Senator's car, xXx's base is raided by a SWAT team and he is drugged.

xXx awakes in a diner where a robbery seemingly begins taking place, but he easily thwarts it. Gibbons then appears to tell him it was a test, which he has passed. xXx isn't interested, but is again drugged. This time he finds himself on a plane with other criminals. They are dumped in Columbia, and come across a cocaine plantation where they are captured by the drugs cartel. At first xXx believes this is another set-up, but as events become serious, he realizes it's for real and escapes when the Colombian Army move in, only to be captured again by NSA agents.

Again, Gibbons tells Cage that exposing the cartel was yet another test. He then gives Cage a choice - work for the NSA or go to prison for a long time. Cage agrees to work for him. He is sent uncover to the Czech Republic and infiltrates Anarchy 99. The leader of Anarchy 99 is Yorgi, an Russian ex-soldier. xXx finds himself attracted to Yorgi's apparent girlfriend, Yelena, and he negotiates political asylum for her, so she can live in America. Anarchy 99 are planning a series of chemical weapons attacks on major cities. They plan to use a sea-faring drone, Ahab, to launch the attacks. xXx works with Czech Special Forces to raid Yorgi's base, chaos ensues and Yorgi and his cohort escape. xXx hunts them down and kills them. After this xXx tracks down the drone, para-sails onto it and destroys it.

The story ends with xXx and Yelena vacationing in Bora Bora. Whilst there, Gibbons informs xXx that something else has come up....