The invention of a machine that can cause remote explosions brings the attention of Scotland Yard and Bulldog Drummond.

John Howard
as Captain Hugh C. Drummond

Heather Angel
as Phyllis Clavering

H.B. Warner
as Colonel Nielsen

Reginald Denny
as Algy Longworth

E. E. Clive
as Tenny

Jean Fenwick
as Lady Beryl Ledyard

Zeffie Tilbury
as Aunt Meg

George Zucco
as Rolf Alferson

Leonard Mudie
as Richard Gannett

Evan Thomas
as Smith