Kieron Moore
Cmdr. Michael Haydon
Lois Maxwell
Kim Hamilton
Donald Wolfit
Prof. Merrity
Bryan Forbes
Jimmy Wheeler
Jimmy Hanley
Larry Noble
Walter Hudd
Professor Blandford
Donald Gray
Captain Ross
Ronan O'Casey
Reporter
Robert O'Neil
Reporter
Alan Gifford
Colonel Galloway
Carl Jaffe
Professor Bechstein
Bill Nagy
Reporter (uncredited)
Trevor Reid
Simmons the Technician (uncredited)
Bernard Bresslaw
Technician (uncredited)
Alastair Hunter
Technician (uncredited)
Barry Keegan
Lefty
Thea Gregory
Barbara Noble
Shirley Lawrence
Ellen
Peter Neil
Tony
Ryck Rydon
Reporter
Charles Richardson
General Barnett
Leonard Sharp
Thomas the Watchman (uncredited)
Paul Beradi
Reporter (uncredited)
Patrick Halpin
Reporter (uncredited)
Terry Randall
Reporter (uncredited)
Terry Randall
Reporter (uncredited)
John Wilder
Reporter (uncredited)
Johnny Wyne
Reporter (uncredited)
Jane Dore
Young Girl (uncredited)
Frank Sieman
Gatekeeper (uncredited)
John Baker
Official (uncredited)
Tony Quinn
Jack the Barman
Tony Quinn
Jack the Barman (uncredited)