Desperate to protect his job from a bureaucratic rival, the head of the French secret service (Jean Rochefort) picks outs a stranger, François Perrin (Pierre Richard), from a Paris crowd and singles him out as a master spy who should be tracked very closely. In reality, François is an amiable, if clumsy, classical violinist whose complete obliviousness to the agents watching him only further convinces them that they have a major undercover operative in their sights.