England, at the start of World War Two. Mysterious wireless broadcasts, apparently from Nazi Germany are heard over the BBC. They warn of acts of terror in England, just before they take place. Baffled, the Defense Committee call in Sherlock Holmes.
as Sherlock Holmes
as Doctor Watson
as Kitty
as Sir Evan Barham
as R.F. Meade
as Sir Anthony Lloyd
as General Jerome Lawford
as Admiral Sir John Fabian Prentiss
as Captain Roland Shore
as Mrs. Hudson
as Jill Grandis
as Camberwell
as Smithson - Barham's Butler (uncredited)
as Meade's Henchman (uncredited)
as BBC Radio Announcer (voice) (uncredited)
as Voice of Terror (voice) (uncredited)
as Bar Patron (uncredited)