In this comedy drama Dr. Clitterhouse is a famed author and criminologist with a keen interest in the physiological responses experienced by crooks when they commit their crimes. To figure it out, he decides to try committing a few jewel thefts. He then gets in touch with a notorious fence so he can dispose of the loot. The lovely fence in turn introduces Clitterhouse to Rocks Valentine, the criminal mastermind behind a gang of master crooks. The good doctor ends up masterminding several major heists for the gang and this causes the real gang leader to become jealous and lock the hapless doctor in a cold-storage vault during a fur heist. Fortunately, the leader's second in command rescues Clitterhouse who decides to go straight and return to his practice. Unfortunately, the vengeful crime boss blackmails him into continuing his crime spree. Clitterhouse pretends to go along with it and pours a drink for the gangster. It contains poison and as the crook dies, the doctor and his nurse record every last spasm. He then turns himself in and pleads guilty by reason of insanity in court. Later he claims the he was sane and did it all in the name of science. The jury judges him nuts and he goes free.