Mills attended the National Youth Theatre for four years and graduated from The Rose Bruford College of Speech and Drama in 1977.
He has appeared on various television programmes such as Minder, Brookside, Play for Today, Waiting for God and the ITV detective series Vera.
In 2019, Mills appeared in the West End as the narrator of the musical 'Call me Diana' based on the life of the Princess.
In 2022 he hosted ‘Sunday at the Musicals’ in London, Eastbourne and Windsor as well as being reunited with Dame Esther Rantzen presenting a successful series of podcasts entitled That's After Life.
[1] He is a patron of The Holly Lodge Centre in Richmond Park and Chairman of The Wimbledon Village Business Association.