Benedict Cumberbatch
Alan Turing
Keira Knightley
Joan Clarke
Matthew Goode
Hugh Alexander
Rory Kinnear
Detective Robert Nock
Allen Leech
John Cairncross
Matthew Beard
Peter Hilton
Charles Dance
Commander Denniston
Mark Strong
Stewart Menzies
James Northcote
Jack Good
Tom Goodman-Hill
Sergeant Staehl
Steven Waddington
Superintendent Smith
Ilan Goodman
Keith Furman
Jack Tarlton
Charles Richards
Alex Lawther
Young Alan Turing
Jack Bannon
Christopher Morcom
Tuppence Middleton
Helen
Dominic Charman
Sherborne Student 1
James G. Nunn
Sherborne Student 2
Charlie Manton
Sherborne Student 3
David Charkham
Joan's Father
Victoria Wicks
Joan's Mother
Andrew Havill
Teacher
Laurence Kennedy
Headmaster
Tim van Eyken
MI6 Agent
Will Bowden
Military Policeman
Miranda Bell
Margaret
Tim Steed
Electrical Assistant
Bartosz Wandrykow
Crossword Enthusiast
Hayley Joanne Bacon
Woman in Crowd (uncredited)
Nicholas Blatt
Ministry Man (uncredited)
Ancuta Breaban
Wren (uncredited)
Alex Corbet Burcher
Dancer (uncredited)
Grace Calder
Assistant Wren (uncredited)
Richard Campbell
Crossword Man in Pub (uncredited)
Daniel Chapple
MI6 Agent (uncredited)
Lisa Colquhoun
Joan Clarke's Friend (uncredited)
Alexander Cooper
Bletchley Park Agent (uncredited)
Leigh Dent
Passerby (uncredited)
Sam Exley
Military Policeman 3 (uncredited)
Denis Koroshko
Civilian (uncredited)
Debra Leigh-Taylor
Evacuee (uncredited)
Stuart Matthews
Bletchley Park Operative (uncredited)
Joseph Oliveira
MI6 Agent (uncredited)
David G. Robinson
Police Sergeant White (uncredited)
Mark Underwood
Crossword Man (uncredited)
Nicola-Jayne Wells
First Aid Nurse (uncredited)
Josh Wichard
German Pilot (uncredited)