In The Talons of Weng-Chiang, he played the conductor of the Palace Theatre. (DOC: The Last Hurrah) He also composed the theme tune to Blake's 7. Simpson's time with Doctor Who came to an end when incoming producer John Nathan-Turner invited him out for lunch one day, during which he announced his intention to dispense with Simpson's services and make a fresh start for the 1980s. All incidental music from then on was composed in-house by the BBC Radiophonic Workshop.