The Riddle of the Sphinx (Inside No. 9) was characterised by Pemberton as a thriller in the style of Anthony Shaffer's 1970 play "Sleuth", while Shearsmith identified the episode as particularly theatrical, in the style of "Sleuth" and Ira Levin's 1978 play "Deathtrap". BBC executives, according to Shearsmith, saw the episode as a cross between "Sleuth" and Willy Russell's 1980 play "Educating Rita" that read as if it had been authored by psychopaths. The executive producer Jon Plowman suggested that the first half of the episode plays out like a radio play. The word-play and tea-drinking in this part of the episode are, in the writers' opinion, very
Walter Shirley Shirley Doncaster.He was educated at Rugby School and Balliol College, Oxford. He was called to the bar at Inner Temple and went on the North Eastern circuit. He wrote several papers on legal matters. At the 1885 general election Shirley was elected as Member of Parliament (MP) for Doncaster. He was an advanced Liberal. He resigned the seat in February 1888 but died in May that year at the age of 36. In the 1886–87 football season, he became the first president of Doncaster Rovers football club. Walter Shirley Shirley Walter Shirley Shirley (1851 – 1 May 1888) was an English