Retired from active duty, and training recruits for the Impossible Mission Force, agent Ethan Hunt faces the toughest foe of his career: Owen Davian, an international broker of arms and information, who's as cunning as he is ruthless. Davian emerges to threaten Hunt and all that he holds dear – including the woman Hunt loves.

Hiller, a computer expert, was bribed by group of bank robbers to obtain details of the security system at a newly-built bank. Having obtained the information, he thought he'd seen the last of the robbers. But now they've traced him and his son to London. They hold the son hostage and force Hiller to decode the information about the alarm and then to take part in the robbery.