A hapless orchestra player becomes an unwitting pawn of rival factions within the French secret service after he is chosen as a decoy by being identified as a super secret agent.

Pierre Richard
as François Perrin

Bernard Blier
as Colonel Bernard Milan

Jean Rochefort
as Colonel Louis Toulouse

Mireille Darc
as Christine

Paul Le Person
as Perrache

Jean Carmet
as Maurice Lefebvre, Perrin's best friend

Colette Castel
as Paulette Lefebvre

Maurice Barrier
as Chaperon, Toulouse agent

Robert Dalban
as Coco, fake delivery man

Robert Castel
as Georghiu, Milan agent