Ring of Spies

Ring of Spies also known as Ring of Treason is a 1964 British spy film based on the reallife case of the Portland Spy Ring, whose activities prompted Reds under the bed scare stories in the British popular press in the early 1960s.

TV Guide gave the film 2.5 out ofstars, and noted that the film concentrates on factual evidence leading up to the crack in the case. Lending an air of authenticity, shots of the actual spies appear in the opening frames, and concluded that despite the documentary flavor, there are a few witty touches by the hand of Tronson while David Parkinson in the Radio Times gave itout ofstars, and felt the docudramatic style rather undermines director Robert Tronsons attempts to build suspense, but Frank Launder proved himself to be just as capable of turning out a nailbiting thriller, as he was of crafting a chortleworthy comedy. For once, separated from his usual partner, Sidney Gilliat although the latters brother Leslie acted as producer, Launder and cowriter Peter Barnes capably retell the story of the Portland spy ring.

Source: Wikipedia