Lothar Gündisch

A scientist invents a serum that keeps a dog's head alive after its body dies. When the scientist dies of a heart attack, his crazed assistant cuts off his head and, using the serum, keeps the doctor's head alive and forces it to help him on an experiment to give his hunchbacked nurse assistant a new body.

Both Scotland Yard and an amateur American sleuth are tracking a master criminal known as The Frog. This moniker refers to the bulging-eyed mask worn by the evildoer, and is reflected by the frog icons painfully tatooed onto the forearms of his henchmen. The trail leads to the country manor of an enigmatic, steely-eyed nabob, whose repressed son has eyes ...