Cast 15

1. 

   Steven Mackintosh

   Himself - Narrator

2. 

   Brian Deacon

   Gordon Welchman (voice)

3. Rosamund Welchman

   Herself - Gordon Welchman's Daughter

4. W. Gordon Welchman

   Himself - Ex-Head of Hut 6, Bletchley Park (1939-1941) (archive footage)

5. Sinclair McKay

   Himself - Author, 'The Secret Life of Bletchley Park'

6. Jimmy Thirsk

   Himself - Veteran, Hut 6

7. Asa Briggs

   Himself - Veteran, Hut 6

8. Jane Fawcett

   Herself - Veteran, Hut 6

9. Tony Comer

   Himself - GCHQ Historian and Former Analyst

10. John Naughton

    Himself - Vice President, Wolfson College, Cambridge (as Prof John Naughton)

11. John Scarlett

    Himself - Chairman, Bletchley Park Trust, and Former Chief, MI6 (as Sir John Scarlett KCMG OBE)

12. Jennifer Welchman

    Herself - Gordon Welchman's Granddaughter

13. Robert R. Everett

    Himself - Former President, The MITRE Corporation

14. Eric Ellingson

    Himself - Gordon Welchman's Colleague

15. Larry Hill

    Himself - Gordon Welchman's Colleague

Crew 2