S5, E3: Nelson Brenner, an advertising consultant who leads a double life as a top domestic spy, sends his former partner on an assignment to recover microfilm from a foreign agent. In reality, Brenner actually sets up his ex-partner, code name Geronimo, for a homicide that Brenner masks as a mugging. When Columbo investigates the crime, his clues lead him through a series of mysterious identities and a maze of domestic intrigue.