[1] He is notable for pioneering, in the early 1980s, the production of independently-made low-budget films made for the home video market.

[1] In the early 1960s Twemlow began a successful career composing library music under the names Peter Reno and John Agar.

His music was used in TV programmes (e.g., Public Eye, Rutland Weekend Television, The Benny Hill Show, Queenie's Castle , The Sweeney), feature films (e.g., Zeta One (1970), Secrets of Sex (1970), Deathdream (1974), A Touch of the Sun (1979), Dawn of the Dead (1978)) and TV commercials.

He wrote two novels: The Pike (1982),[6] of which he announced a film version[7][8][9] but failed to secure funding,[10][11] and The Beast of Kane (1983).

Grievous Bodily Harm,[13] one of the earliest British films to be shot on video, which sold over 10,000 copies in its first month of release.