A sophisticated jewel thief tries to prove himself innocent of a string of cop murders.

Wealthy scion Peter DeHaven, about to marry socialite Christine Lunceford, wakes up after bachelor party revelry to find he's been turned invisible by eccentric college professor Reginald Shotesbury. An unbelievable series of events is revealed by several witnesses testifying in a "mystery trial" to determine the reason for DeHaven's "disappearance".

Humble stamp dealer Otto Becker has little to do with international politics, so when he receives a surprise visit from his estranged twin brother and Nazi spy, Baron Hugo von Detner, his world is thrown into turmoil. Threatening Becker with deportation, Hugo forces him to use his shop as a front for espionage.

Moriarty is sentenced to death, and Sherlock Holmes prepares to retire to the country and marry his girl. But Moriarty has sworn that Holmes, Lt. Col. Gore-King of Scotland Yard, and his trial judge shall all be hanged too. When Moriarty escapes and proceeds to put his threat into operation, Holmes has to postpone his retirement.

While on trial for her life, a young woman recalls her tough upbringing and her involvement with the men who brought her to this current state of affairs.

A millionaire automaker retires upon the advice of his doctor, but becomes so bored he buys half interest in a gas station and works it on the sly.

A mother wishes for the return of her dead son, a wish that is granted by the severed paw of a dead monkey.