The Long Arm

Scotland Yard detectives attempt to solve a spate of safe robberies across England beginning with clues found at the latest burglary in London. The film is notable for using a police procedural style made popular by Ealing in their 1950 film The Blue Lamp. It is known in the US as The Third Key.

• 
  Charles Frend

• 
  Jack Hawkins
  Supt Tom Halliday
• 
  John Stratton
  Sergeant Ward
• 
  Dorothy Alison
  Mary Halliday
• 
  Michael Brooke
  Tony Halliday
• 
  Sam Kydd
  Police Constable in Information Room
• 
  Glyn Houston
  Detective Sergeant in 'Q' car
• 
  Richard Leech
  Nightwatchman / Gilson
• 
  Newton Blick
  Deputy Commander
• 
  Geoffrey Keen
  Chief Superintendent Jim Malcolm
• 
  Sydney Tafler
  Stone
• 
  Peter Burton
  Creasey
• 
  George Rose
  Slob
• 
  Arthur Rigby
  Detective Inspector at Chester
• 
  Ralph Truman
  Colonel Blenkinsop
• 
  Ian Bannen
  The Young Workman - Stanley James
• 
  Maureen Davis
  The Young Workman's Wife - Mrs. James
• 
  John Warwick
  Detective Inspector at Shipping Office
• 
  Joss Ambler
  Cashier at Shipping Office
• 
  Barry Keegan
  Detective Constable in Hospital Ward
• 
  Alec McCowen
  House Surgeon