Shadow of Doubt (1957)

A nuclear physicist, Dr Ross, seeks to return to his lab after serving five years in prison for breaching the Official Secrets Act (he told secrets to an ex-student, Fletcher, with certain political beliefs). Disgraced and friendless, he can only get work as a clerk. He lives with his wife Laura under the new surname of "Denver". Laura works as a nurse. The man upstairs, Frank, was a former agent. They live as boarders in a house owned by Gladys and Hughie, a working class couple, who believe that Arthur was ill in a sanatorium. Manning, the MI5 responsible for Arthur's original arrest, arrives with news that Ross' identity is about to be revealed in a newspaper article. (Frank has been keeping an eye on Arthur for Manning.) The information comes out and Arthur is fired from his job. Manning tells Arthur he will be approached from the other side. Word gets out and journalists start approaching. Gladys and Hughie ask the couple to leave. Laura is worried she will lose her job. They are approached by a man, Cantrup, who offers him a job as a researcher on a project in Ireland. Arthur accepts but Laura worries this is the offer Manning warned them about. She suggests he check with Manning but Arthur refuses.