In this episode there are other Guest Cast appearances.  I am not sure how to list them under the normal Guest Cast listing so I will list them here.  Please feel free to include these actors in their rightful category if you know how. Here is how they appeared in the credits:

Kabuki Theatre Scenes Staged by Harold Cheshire

Cast

Tudor Davis                    Hamlet

Clive Marshall                 Laertes

Vernon Morris                 Sword Bearer

Daniel Nicolaides           Queen

Graham Payne               Korombo

Stewart Rose                 Korombo

Kenneth Shanley            Horatio

Kit Williams                    Korombo

Richard Wilson              King

Also of note:    Pimlico Films wish to thank the directors and staff of Radio 390 for their cooperation.

This blurb was in the end credits of the episode.

Episode Synopsis: Drake poses as a manservant to infiltrate a wealthy couple to see who and how government secrets are being passed to agents who sell the information to the highest bidder.

Episode synopsis:  A British general's son-in-law is being blackmailed and he elicits Drake's help to ferret out the blackmailer. Whilst Drake is trying to unravel who's behind the blackmailing, he discovers there is more to it than a simple blackmail.  It seems that there is a black book that the other side will do anything to get back.