Industrialist François Delambre is called late at night by his sister-in-law, Helene Delambre, who tells him that she has just killed her husband, André. Reluctant at first, she eventually explains to the police that André invented a matter transportation apparatus and, while experimenting on himself, a fly entered the chamber during the matter transference.
An escaped convict, injured during a robbery, falls in love with the woman who nurses him back to health, but their relationship seems doomed from the beginning.
A tough cop meets his match when he has to guard a gangster's widow on a train journey from Chicago to Los Angeles.
