British diamond smugglers use the radiowoman (Phyllis Kirk) from a freighter docked on the Thames to unwittingly "mule" their swag, hidden in cigarettes, past customs, not knowing that she has befriended an Inspector for the Thames River Patrol.
Top Cast
John BentleyDet. Insp. Dan Barker
Phyllis KirkJudy Roberts
Leonard WhiteDet. Sgt. Mack McLeod
Glyn HoustonCharlie Williamson
Patrick JordanAlbert Fisher, called both "Al" and "Bert"
Harold AyerSteward Alfred Gordon, also called "Al"