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 Marriott
        Virginia Maskell ... Dr. Lucy Byrne
        Ian Bannen ... Alan Andrews
        Kenneth Griffith ... Dr Shole
        Peter Cushing ... Professor Sewell
        Thorley Walters ... Special Agent Prince
        Donald Pleasence ... Parsons, alias Bill Brown
        Spike Milligan ... Arthur, lab orderly
        Raymond Huntley ... Sir George Gatting, the Minister of Defense
        Sam Kydd ... Slater
        Anthony Booth ... Parkin
        Basil Dignam ... Dr.Childs
        Brian Oulton ... Director
        Robert Bruce ... Levers
        John Payne ... Iverson