British Intelligence officer Maj. Richard Mace drafts five unwilling criminals Rocca, Scanlon, Durell, Fell, and Saval, all experts in a variety of the criminal arts, for a secret mission. The mission: infiltrate Dubrovnik and rescue an imprisoned Italian general, who has changed sides and turned to the Nazis, to convince his troops to turn against Hitler.
They are smuggled into Yugoslavia and once in Dubrovnik, however, the soldiers are captured and thrown into prison. Coincidentally, the prison houses the Italian general they seek; so when they escape, they drag the strangely resistant general with them.
Soon they learn that the general is an impostor who replaced the real general after he was murdered by the Nazis. Determined to complete their mission, the soldiers haul the impostor before the Italian troops and force him to tell them to fight against Hitler. Halfway through the speech, the imposter begins shouting pro-Nazi propaganda. Silva, dressed as a Nazi, spouts his own Third Reich rhetoric and guns the general down in front of his troops. The angry troops decide that the Nazis cannot be trusted and take up arms against the Axis, making the mission a success.