Mr Benn is a character created by David McKee who originally appeared in several children's books. The first, Mr Benn Red Knight, was published in 1967, followed by three more; these became the basis for an animated television series of the same name originally transmitted by the BBC in 1971 and 1972.

In both the books and the television series, Mr Benn's adventures take on a similar pattern. Mr Benn, a man wearing a black lounge suit and bowler hat, leaves his house at 52 Festive Road, London, and visits a fancy-dress costume shop where he is invited by the moustachioed, fez-wearing shopkeeper to try on a particular outfit. He leaves the shop through a magic door at the back of the changing room and enters a world appropriate to his costume, where he has an adventure (which usually contains a moral) before the shopkeeper reappears to lead him back to the changing room, and the story comes to an end. Mr Benn returns to his normal life, but is left with a small souvenir of his magical adventure. Additionally, scenes before and after his adventure usually have some connection to it, such as the games the children are playing in the street as he passes.

David McKee got the inspiration for Mr Benn from Festing Road in Putney where he used to live. McKee had the house "next door" at 54 Festing Road, where residents installed an engraved paving slab in his honour on 26 November 2009. ("I think it was because in the first book I drew myself looking out of the window, and I thought it would be quite nice to have him next door", said McKee.)^[1]

McKee said he had always thought of Mr Benn as having the first name William.^[2][3]

Mr Benn's adventures are available to buy in book-form: four were published originally, and further books in the 1990s were based on the television series. The original four books were: Mr Benn – Red Knight, Big Game Benn, 123456789 Benn, and Big Top Benn. There were six original books planned, but the fifth and sixth were never published. The fifth was called Mr Benn Rides Again, the story of which was used to make the television episode The Cowboy. The sixth, never completed, was Superbenn, in which the superhero Mr Benn sets out on an environmental adventure.^[4]

There is one book for which no corresponding television episode has (yet^[update]) been made. 123456789 Benn was published in 1970 (ISBN 0-234-77361-8) and tells the story of Mr Benn as a convict (hence the number) inspiring his jail-mates to brighten up their cells. This was after the BBC – who screened the television series – felt that the story was too mature for a children's series.^[5]

A new story was published in 2001, the first Mr Benn story that McKee had written in thirty years, and is called Mr Benn – Gladiator (ISBN 1-84270-024-3). McKee indicated that he might write more Mr Benn stories, but none were published before his death.^[6]

In 2001 Mr Benn's Little Book of Life was published by Tess Read, which explores the lessons of Mr Benn's adventures.^[7]

The only character who appears several times, apart from Mr Benn and the shopkeeper, is Smasher Lagru. Smasher first appears as an inmate in 123456789 Benn, and then after his release in Big-Top Benn and the new Mr Benn – Gladiator.

A Mr Benn Annual (ISBN 0-85096-029-0) was published by Polystyle Publications Ltd in 1972. It was written by Jan Falconer and illustrated by David McKee. This contained a number of illustrated text stories, three strip-cartoon style adventures and a few puzzle pages. Mr Benn visits: China for a kite festival, a fairytale Arabia, Venice and Holland. He also becomes a barrow boy in a pearly suit and meets Mr Grubbly and his animal friends in the African jungle.

Tate Publishing republished all of the original books in 2010.

McKee wrote and animated (with Ian Lawless) thirteen Mr Benn episodes for the BBC between 1971 and 1972. These episodes were repeated twice a year for 21 years^[8] with further repeats airing in 1993, 1994, 1996, 1997, 1998 and 2000.^[9] The episodes were narrated by Ray Brooks. The music is credited as composed by Don Warren, which was a pseudonym for Duncan Lamont.^[10]

Although Smasher Lagru features in The Gladiator, he does not appear in The Clown as the book in which he made his debut, 123456789Benn, was not adapted for television – thus it would have been strange that he and Mr Benn already knew each other. The Hunter was also slightly altered; the book Big Game Benn features several hunters, but only one appears in the television episode.

McKee did not benefit financially to the extent he might have: "I signed a contract where I only got a one-off payment and no repeat fees, but I've done quite well from a number of other things and I'm still exhibiting paintings."^[11] According to Mr Benn's Little Book of Life, very little of McKee's original artwork created for the television episodes exists today, as most of it was thrown into a rubbish skip in the 1970s.

After over thirty years, a brand new Mr Benn episode was screened for the first time on 1 January 2005, on Nick Jr. UK's evening block Noggin. The episode was based on McKee's 2001 book Mr Benn - Gladiator.

The series was voted the sixth most popular children's television programme in the 2001 Channel 4 poll 100 Greatest Kids' TV shows. It was also rated number 13 in the 50 Greatest Kids TV Shows which aired on Channel 5 on 8 November 2013.