Two newly-appointed postal inspectors, Frank Marshall and 'Slim" Hewitt, set out to track down the sender of a time-bomb to a U. S. Senator and, during their investigation, run across a hooded organization that is terrorizing an American city. They also meet Don Foster, who is loud in his condemnation of the terrorists, and his sister, Nancy, who fears for her brother's life.
Bruce Cabot
as Frank Marshall
Marguerite Churchill
as Nancy Foster
Crawford Weaver
as Slim Hewitt
Ward Bond
as Don Foster
Charles C. Wilson
as Colonel McCollum (as Charles Wilson)
John Hamilton
as Cummings
Arthur Loft
as Gardner
Nick Copeland
as Lefty (as Nicholas Copeland)
John Tyrrell
as Feeney (as John Tyrell)
