"Sherlock Holmes and Doctor Watson get involved with Balkan terrorists to save Emperor Franz Joseph I of Austria from an assassination at the opera house and prevent World War I."
Christopher Lee
as Sherlock Holmes
Patrick Macnee
as Dr. Watson
Morgan Fairchild
as Irene Frances Adler
John Bennett
as Sigmund Freud
Michael Siberry
as Franz Winterhauser
Dominic Jephcott
as Major Von Bork
Frank Middlemass
as Dr. Froelich
James Bree
as Franz Dietrich
Tom Chadbon
as Zygovich
Paul Humpoletz
as Hugo Oberstein
Tom Lahm
as Elliott Ness
Ronald Hines
as Reginald Cholmondley
Nicholas Gecks
as Michael Simpson-Makepeace
Jenny Quayle
as Violet Cholmondley
Charlotte Attenborough
as Margaret Froelich
Kalman Glass
as Franz Zimmer
Robert Rietti
as Franz Hoffman
Terence Beesley
as Serge Duvok
Patrick Monckton
as Laszlo Karparti
Leon Lissek
as Stage Door-Keeper
Cyril Shaps
as Franz Joseph
Guy Scantlebury
as Captain Melbury
Jerome Willis
as Mycroft Holmes
Margaret John
as Mrs. Hudson
Michael McStay
as Inspector Schmidt
Engelbert Humperdinck
as Eberhardt Bohm
Peter Sasdy
Director
Arthur Conan Doyle
Characters
Bob Shayne
Writer
Harry Alan Towers
Executive Producer
Detto Mariano
Original Music Composer
H.R.F. Keating
Brian West
Cinematography