When a corpse is found in the Thames, the only clue is that the dead man was killed by a karate or judo expert.
John Bentley
as Superintendent Wills
Patrick Allen
as Dr. Nelson Pollard
Jacqueline Ellis
as Elsa Marlowe
Wilfrid Brambell
as Lock-Keeper
John Glyn-Jones
as Dr. Maurice Tarn
Jane Murdoch
as Honeymoon Wife
Brian McDermott
as Det. Sgt. Stillman
Gerald Andersen
as Major Paul Amery
Edward Atienza
as Clerk
Ric Young
as Johnny Choto
Robert Lee
as Mr. Nam Lee
Yvonne Buckingham
as Miss Russell
