Enjoying an enviable bachelor lifestyle, the former super-agent and now suave playboy photographer, Matt Helm, finds himself back in action, when MacDonald, the head of the Intelligence and Counter Espionage secret agency, visits him. With the evil Chinese agent, Tung-Tze, and his underground terrorist organisation known only as "The Big-O" behind a murderous scheme to blanket the South-western United States with a radioactive cloud, Matt has less than two days to thwart the criminal mastermind's plans for world domination. Now, armed with a wide array of ingenious counter-espionage gadgetry, Matt and his well-meaning but not-so-helpful assistant--the beautiful barmaid, Gail Hendricks--will have to avert the impending catastrophe single-handedly. Can the man from I.C.E. save the day?