Cast
Doctor B. N. Wallis, C.B.E., F.R.S.
Mrs. Wallis
Doctor
Sir David Pye, C.B., F.R.S.
Doctor W. H. Glanville, C.B., C.B.E.Committee Member Committee Member Committee Member 
Official, National Physical Laboratory
Official, Ministry of Aircraft Production
Captain Joseph (Mutt), Summers, C.B.E.
Observer At TrialsObserver At Trials R.A.F. Officer At Trials 
Air Chief Marshal Sir Arthur Harris (now Marshal of the Royal Air Force), G.C.B., O.B.E., A.F.C.
Air Vice-Marshal The Hon. Ralph Cochrane (now Air Chief Marshal), G.B.E., K.C.B., A.F.C.
Group Captain J. N. H. Whitworth, D.S.O., D.F.C.
Farmer
Group Signals OfficerB.B.C. Announcer 
Wing Commander Guy Gibson, V.C., D.S.O., D.F.C.Flt / Lt. R. D. Trevor-Roper, D.F.C., D.F.M. Flt / Lt. R. E. G. Hutchison, D.F.C. 
Flying / Off. F. M. Spafford, D.F.C., D.F.M.Flt / Lt. A. T. Taerum, D.F.C. 
Flt / Sgt. J. Pulford, D.F.M.Plt / Off. G. A. Deering, D.F.C. 
Squadron Leader H. M. Young, D.F.C.
Squadron Leader H. E. Maudslay, D.F.C.
Flight Lieutenant J. V. Hopgood, D.F.C.Flight Lieutenant W. Astell, D.F.C. 
Flight Lieutenant H. B. Martin, D.S.O., D.F.C., A.F.C. (now Wing Commander)
Flight Lieutenant D. J. H. Maltby, D.S.O., D.F.C.Flight Lieutenant D. J. Shannon, D.S.O., D.F.C. (later Squadron Leader) Flying Officer L. G. Knight, D.S.O. Flight Lieutenant R. C. Hay, D.F.C. 
Flight Lieutenant J. F. Leggo, D.F.C.
Flight Sergeant G. E. Powell
Wing Comdr. Gibson's Batman
Crew member, not listed in creditsCrew Member, not listed in credits RAF Officer, not listed in credits 
Tail Gunner, not listed in credits
Mocking RAF Officer, not listed in credits
RAF Pay Clerk In NAAFI, not listed in credits
Collins, not listed in credits
Flight Sergeant, not listed in credits
Guard on Door, not listed in creditsWaiter, not listed in credits Barnes Wallace's Daughter, not listed in creditsа 
RAF Officer, not listed in credits
