The Black Sheep of Whitehall (the opening credits read Black Sheep of Whitehall) is a 1942 British black-and-white comedy war film, directed by Will Hay and Basil Dearden, starring Will Hay, John Mills, Basil Sydney and Thora Hird in her screen debut. It was produced by Michael Balcon and Ealing Studios. Plot When he is forced to vacate the office of his debt-ridden correspondence college, 'Professor' Will Davis (Will Hay) goes to the Ministry of International Commerce at Whitehall in order to confront his one-and-only student, PR man Bobby Jessop (John Mills). To get Davis off his back, Jessop proposes to get him a job at Whitehall. Jessop then leaves in order to fetch a Professor Davys at the railway station. The professor is a leading economist who has returned from a long stay in South America in order to advise the British government on a trade treaty with the South American nations, which could be crucial to Britain's war effort. The clueless Davis is mistaken for the expert and gets involved in a series of interviews, giving answers based on gambling, con jobs, double entendres or just plain ignorance. These scenes are very funny and are made more so by the reactions of an increasingly incredulous Joss Ambler as government minister 'Sir John'. Jessop later returns with 'Professor Davys' and the confusion is sorted out, though it has left the BBC interviewers in a state of mental collapse. Jessop then discovers that the man he brought with him is in fact Crabtree (Felix Aylmer), a member of a group of fifth columnists working for Nazi Germany. Jessop promises Davis a job if he will help him track down the real Professor Davys (Henry Hewitt), who is being held in a safe house by Crabtree's associates. Assuming a number of disguises, Davis and Jessop set off to foil the plot before the treaty is compromised. Main cast Will Hay as Will Davis John Mills as Bobby Jessop Basil Sydney as Costello Henry Hewitt as Professor Davys Felix Aylmer as Crabtree Owen Reynolds as Harman Frank Cellier as Dr Innsbach Joss Ambler as Sir John Frank Allenby as Onslowe Thora Hird as Joyce Margaret Halstan as Matron Barbara Valerie as Sister Spooner Leslie Mitchell as Radio interviewer George Woodbridge as Male Nurse George Merritt as Stationmaster Aubrey Mallalieu as Ticket Collector Kenneth Griffith as Butcher's Boy Cyril Chamberlain as BBC Producer