"When a government official disappears in the London tunnels, after several reports of missing people in the same location, Scotland Yard start to take the matter seriously, along with a couple who stumble into a victim by accident."
Donald Pleasence
as Inspector Calhoun
Norman Rossington
as Det.Sgt. Rogers
David Ladd
as Alex Campbell
Sharon Gurney
as Patricia Wilson
Hugh Armstrong
as The "Man"
June Turner
as The "Woman"
Clive Swift
as Inspector Richardson
James Cossins
as James Manfred O.BE.
Heather Stoney
as P.C.W. Alice Marshall
Hugh Dickson
as Dr. Bacon
Christopher Lee
as Stratton-Villiers, MI5
Jack Woolgar
as Platform Inspector
Ron Pember
as Lift Operator
Colin McCormack
as Police Constable 1
Gary Winkler
as Police Constable 2
James Culliford
as Publican
Suzanne Winkler
as Prostitute
Gerry Crampton
as Tunnel Worker
Terry Plummer
Gordon Petrie
Gary Sherman
Director
Ceri Jones
Screenplay
Paul Maslansky
Producer
Geoffrey Foot
Editor
Mary Selway
Casting
Dennis Gordon-Orr
Art Direction
Harry Frampton
Makeup Artist
Peter Frampton
Alex Thomson
Director of Photography
Joyce Herlihy
Production Manager
Tony Teiger
Property Master
Lewis More O'Ferrall
Assistant Director
John Hackney
Sound Editor
David Cadwallader
Key Grip
Dave Clarke
Electrician
Colin Corby
Camera Operator
John Golding
Focus Puller
Kay Rawlings
Continuity
Original Story
Wil Malone
Original Music Composer
Jeremy Rose