Underdog rescues a boy locked in a bank vault, causing destructive mayhem in the process; An army of huge mechanical monsters invades the city and capture Polly Purebred; Simon Bar-Sinister develops an energy ray that turns its target into a photograph. He kidnaps Sweet Polly Purebred to trap Underdog into a photograph and tear him up; The Indian Gophers plan to send the colonel to the moon in a rocket; Commander McBragg tells how he untrailed a group of savages