Producer: Bruce Lansbury
Writer: Ken Pettus
Director: Herb Wallerstein

Jim Phelps: Peter Graves
Paris: Leonard Nimoy
Dana Lambert: Lesley (Ann) Warren
Barney Collier: Greg Morris
Willy Armitage: Peter Lupus

Ramon Prado: Fernando Lamas
Arturo Sandoval: Percy Rodrigues

 The IMF is to gain possession of a microfilm. It contains the names of 16 undercover men whose lives will be in jeopardy if it is combined with the other half. Both halves of the film are useless until they are combined. One is in the hands of the largest narcotics dealer, Ramon Prado, the other in the hands of his underworld enemy, Arturo Sandoval. They are arranging for a truce which would result in the combination of the films and in the death of those men. Prado keeps his half on one of the stamps he's collecting and keeps them safe in a bomb prove cellar. 

A sailor, first officer on a ship (Paris), offers Prado a very rare coin in exchange for some stamps. Prado offers him various stamps – except one. When Paris has a look at it he places a tiny oscillator on it's box which produces sound waves no human ear can hear and leaves to fetch his coin. Jim poses as syndicate courier when he meets Sandoval. He warns him of hits against the syndicate and makes it very clear that a combination of the two parts of the films is necessary. In order to get the stamp Chico, the trained dog to fetch things by the sound they send, is crawling though the air ventilation pipe system to get into the safe room. 

Paris comes back to Prado with a fake. Prado's men do a test and find out that the coin is not genuine. It was planned that Paris is heavily beaten up and Barney and Willy hearing what's happening inside while working with Chico have to concentrate on their work. Finally Paris admits his real intentions: to steal the coin because he is in possession of the other half. He claims that anybody else claiming to possess the other part is planning to set Prado up. Barney replaces the part of the microfilm with a film which matches Paris' half and Chico brings back the stamp in it's box. An indecipherable mess is seen when Sandoval arrives and matches his part with Prado's half. In combination with Paris' half of the film names are revealed – amongst them Sandoval's name. When Prado has Sandoval shot, the IMF call the police.