SCREENWRITER and producer Brian Clemens, the man who created some of television's greatest shows, including The Avengers and The Professionals, has died aged 83.

His son George said he died in hospital in London on Saturday.

Clemens started his working life in advertising before breaking into the film and TV industry, writing scripts for low-budget thrillers.

He wrote the original pilot episode for The Avengers, the cult swinging sixties spy show which made stars out of its cast, including Patrick Macnee, Honor Blackman and Diana Rigg. He was also the driving force behind the show's glitzy 1970s relaunch, The New Avengers, which made a star out of Joanna Lumley and, to a lesser extent, Gareth Hunt.

Unfortunately The New Avengers faltered after two seasons. Undeterred, Clemens dusted down an old idea for The A-Squad, a series about a shadowy branch of British intelligence, CI5, called upon to fight terrorism at home and abroad.

Re-titled The Professionals - and starring Lewis Collins, Martin Shaw and Gordon Jackson - the show went on to become Clemens' greatest domestic hit with audiences of more than 15 million.

Both The New Avengers and The Professionals have become enduring classics with fan clubs and websites dedicated to preserving their memory.

Clemens also worked on included Danger Man, Adam Adamant Lives! and The Persuaders, as well as Bergerac and Perry Mason.

He also transferred his talents to the big screen. He wrote the under-rated thriller And Soon The Darkness, starring Michele Dotrice, and a couple of horrors for Hammer: Dr Jekyll and Sister Hyde and Captain Kronos: Vampire Hunter. The latter was set to become a series until the studio went bust.

Croydon-born Clemens, who was awarded an OBE in 2010, was working with his two sons on another horror film when he died.