The Devil's Agent (1962)

The Devil's Agent is a 1962 drama film directed by John Paddy Carstairs and starring Peter van Eyck, Marianne Koch, Christopher Lee and Macdonald Carey. It was a co-production between Britain, West Germany and the Republic of Ireland and was an English-language version of the German film Im Namen des Teufels. It was based on a novel by Hans Habe. It is set in East Germany during the Cold War

More at Wikipedia.