His first film appearance was a starring role in New Zealand film Broken Barrier (1952). Since then, Bayler has spent the majority of his six-decade long acting career in England, although he also appeared in 1981 New Zealand feature Pictures and British Broadcasting Corporation mini-series The Other Side of Paradise (1992), filmed partly in Raratonga. Broken Barrier was the only locally made feature shot in New Zealand during the 1950s.
Bayler starred as a young journalist who falls in love with a Maori woman.
lieutenant was directed by Roger Mirams and John O"Shea – O"Shea went on to direct the only New Zealand feature films made in the 60s, drama Runaway and musical Don"t Let it Get You. Bayler was given stitches above an eye after he was injured in a sword fight with actor Jon Finch (playing Macbeth) during the shooting of Roman Polanski"s 1971 film of Shakespeare"s Macbeth.
Bayler played Macduff. Bayler"s associations with Monty Python date from 1975 when he appeared in Eric Idle"s British Broadcasting Corporation television series Rutland Weekend Television.
Idle also cast him in his play Pass The Butler.
He played the Bloody Baron in the Harry Potter films. He had a small role as Mr. Gregory in Monty Python"s Life of Brian (1979), and appeared in two more of Python member Terry Gilliam"s films, Time Bandits (1981) and Brazil (1985).