Holding a top secret post in the Ministry of Defense, Commander Rimmington, of Her Majesty's Navy, must watch appearances, and he is not always pleased by the carryings-on of his impulsive daughter, Nancy. Her latest escapade begins when her friend, ballerina Alicia Courtney, arrives breathlessly to announce that the great Russian dancer, Petrovyan, has decided to defect to the West-and that she has smuggled him out of London in the trunk of the Commander's car. The first question is how to distract the Commander while Petrovyan is sneaked into the house, but then, after the Commander goes off fishing, the problems really begin to mount. An official appears with a coded message for the Commander and, in an attempt to get rid of him quickly, the Commander is impersonated by Nancy's fiance, Gerry Buss. As they try to hide Petrovyan, the trumped-up stories and assumed identities mushroom hilariously, while agents from the Russian embassy lurk outside in the bushes, the local constable blunders in at the wrong time.