Detective Sexton Blake takes on Nazi spies while solving a series of crimes.
| Actor | Role |
|---|---|
 David FarrarSexton Blake | Sexton Blake |
 Dennis PriceDick Warren | Dick Warren |
 Pamela StirlingStella Duncan | Stella Duncan |
 Julien MitchellJames Duncan (as Julian Mitchell) | James Duncan (as Julian Mitchell) |
 Cyril SmithP.C. Morgan | P.C. Morgan |
 Ferdy MaynePaul Dacier | Paul Dacier |
| DDennis ArundellPhillip Rainsford | Phillip Rainsford |
 Johnnie SchofieldPurvis | Purvis |
| PPaul CroftMarat | Marat |
 Kynaston ReevesBeales | Beales |
 Desmond RobertsCotter | Cotter |
 Danny GreenCarl | Carl |
 Patric CurwenDr. Grey | Dr. Grey |
| TTony ArpinoFox | Fox |
| VVincent HolmanCol. Wills | Col. Wills |
 Howard DouglasPreston | Preston |
| BBilly HowardSergeant Crossby | Sergeant Crossby |
| AAnders TimbergWrexham | Wrexham |
| HH Victor WeskeOtto | Otto |
| GGerald PringSir Horace Cranston | Sir Horace Cranston |
| NNoel DaintonVan Schuster | Van Schuster |
| OOlive WalterHousekeeper | Housekeeper |