[1][2][3] Prior to becoming a sitcom writer he was a reporter for a local weekly paper, the Tottenham Weekly Herald and was also briefly a staff writer for The Sunday Times in the mid- to late 1970s.
[4] He also worked as writer/researcher for Thames Television's current affairs programme, This Week.
Following a chance encounter with comedy writer Barry Took, he and childhood friend Maurice Gran got an opportunity to write a radio show for comedian Frankie Howerd, which led to their becoming full-time comedy writers.
[1] Marks subsequently wrote with Gran the TV comedy-drama Shine on Harvey Moon (1982–85, 1995) and the popular sitcoms The New Statesman (1987–92), Birds of a Feather (1989–98, 2014–2020) and Goodnight Sweetheart (1993–99, 2016).
[6] His father, Bernard Marks, was one of 43 people who died in the Moorgate tube crash of 1975, the deadliest accident on the London Underground.