N. F. Simpson which no episodes survive. His final series for television was the unsuccessful "Charley’s Grants" (1970), co-written with John Fortune and John Wells, starring Hattie Jacques, and produced by Ian MacNaughton (who produced "Monty Python’s Flying Circus"), which is also entirely lost. Plays followed, including a satire on advertising, "Thank You Very Much" (1971), and an effective three-hander for ITV, "Silver Wedding" (1974), directed by Mike Newell. Simpson’s highest-profile production for television was "Elementary, My Dear Watson" (1973), a Sherlock Holmes parody for BBC One’s "Comedy Playhouse" starring John Cleese and Willie Rushton. It has been screened several times at the
John Cleese the fourth season. Despite this, he remained friendly with the group, and all six began writing "Monty Python and the Holy Grail"; Cleese received a credit on three episodes of the fourth series which used material from these sessions, though he was officially unconnected with the fourth series. Cleese returned to the troupe to co-write and co-star in the Monty Python films "Monty Python and the Holy Grail", "Monty Python's Life of Brian" and "Monty Python's The Meaning of Life", and participated in various live performances over the years. From 1970 to 1973, Cleese served as rector of the University