Rock Hudson as New York City police captain Mike Harmon, who becomes involved with sex bomb Esmeralda Marini (Claudia Cardinale). Esmeralda, using the ploy that Harmon was an old friend of her father, convinces him to help her return some hot jewels to their former owners. Soon enough, Harmon and Esmeralda are jetting to Austria, where Harmon disables the victims' home-security system and sneaks the jewels back into their rightful place. But Esmeralda has tricked Harmon into replacing the real gems with fake ones, and now Harmon is a jet-set thief along with Esmeralda. Harmon, having gotten a taste of criminal high life, wants to split fifty-fifty with Esmeralda on the next heist. Esmeralda, however, wants to call it quits and get married. Harmon, doesn't see it that way, and Esmeralda, a one-man woman all the way, follows him as he heads off to his next nefarious adventure.