Doctor in the House S04E10 - Mum's the Word

Professor Loftus believes there should be a junior doctor on the board but only Duncan and Bingham apply. Dick tries to swing things for Duncan by saying that his mother is a countess but Bingham, coincidentally called out to treat her, finds she is a policeman's wife and sends the board to see her. Dick thinks quickly and drags up to impersonate the countess and Duncan gets the post.