Relatively little xenophobia and a lowish body count in this later-period Drummond. A cartel of weapons manufacturers wants a British inventor eliminated before he can build an unbreakable shield around Britain. They call in Irma, consort of the late Carl Peterson, who together with her henchmen has a burning desire for revenge against Bulldog Drummond. The villains infiltrate a house next to the inventor's, but rather than simply blowing him to blazes with high explosive, Irma develops an elaborate plan involving a Drummond impersonator, phone mimicry, and the gradual capture of most of Drummond's strike force plus his wife Phyllis. The weapons manufacturers are getting understandably impatient by the time Irma brings off her masterstroke; but alas, Drummond has seen through the fiendish plan and the police are waiting. Is this the end of femme fatale Irma? Mildly entertaining, if only for the Drummond gang's peculiar drinking habits - alternate beers and martinis.