A government team researching cures for plague find their results put on the Official Secrets list. One of their number is so incensed by this that he lets the maimed and jealous companion of a female colleague draw him into what, technically, could be a treasonable act.Tony Britton ... Dr. Robert MarriottVirginia Maskell... Dr. Lucy ByrneIan Bannen... Alan AndrewsKenneth Griffith... Dr SholePeter Cushing... Professor SewellThorley Walters... Special Agent PrinceDonald Pleasence... Parsons, alias Bill BrownSpike Milligan... Arthur, lab orderlyRaymond Huntley... Sir George Gatting, the Minister of DefenseSam Kydd... SlaterAnthony Booth... ParkinBasil Dignam... Dr.ChildsBrian Oulton... DirectorRobert Bruce... LeversJohn Payne... Iverson