[3][4] The Independent said that, "In the 1990s, through a series of sprawling monologues packed with arcane information and freakish speculations on the nature of reality, he became something approaching a grand old man of the fringe, though without ever discarding his inner enfant terrible.

"[7] The artistic director of the Liverpool Everyman and Playhouse said, "He was the door through which many hundreds of kindred souls entered a madder, braver, brighter, funnier and more complex universe.

[9] He staged his first performances in the bathroom of his childhood home: "I was three years old and helped by my invisible friend, Peter Jelp, I put on shows for the characters in the linoleum.

"[10] He was educated at Chigwell School (where he won the Drama prize) and then studied at RADA before joining Colchester Repertory theatre as an understudy to Warren Mitchell.

Sir Peter Hall, director of the National at the time, writes of Campbell in his Diaries, "He is a total anarchist and impossible to pin down.

"[13] The Warp, based on the real life experiences and adventures of author Neil Oram, is a dizzying trek through the nether reaches of gurudom and tireless post-sixties mind-expansion, directed by Ken Campbell, and opened at London's Institute of Contemporary Arts in January 1979.

Probably the most remarkable, and in terms of the ethos of the author and the work, the most attractive event in this episode was the five marathons that were performed, against the wishes of an army of local officialdom, during a squat of the Regent Theatre in Edinburgh during the Festival of 1979.

Cult status was established giving some credence to the publicity material - "The world may soon divide into those who have been through THE WARP and those who have not" More recently the cycle was revived in the 1990s in a production directed by Campbell's daughter Daisy.

Audience-carrying capacity was not a problem at London's vast Rainbow Theatre where Campbell mounted a yet more grandiose version of The Hitchhiker's Guide in July 1980.

The series provoked such a press outcry at the time that the BBC banned its overseas sale, since it was deemed to have portrayed Britain's police and criminal justice system in such a wholly unfavourable light.

He played Alf Garnett's neighbour, Fred Johnson in the series of the 1980s sitcom In Sickness and in Health, which had the effect of cementing his career-long friendship with Warren Mitchell.

He was memorable in Jack Pulman's 1981 television series Private Schulz as the acerbic Herr Krauss, an underwear factory owner hoping the war would continue so as not to jeopardise his contracts with the German army.

He was beaten to the role by his old protégé Sylvester McCoy, but an independently written and produced episode, "The Lost Doctor", features the voice of Ken Campbell.

Other roles included playing a mad scientist on the children's programme Erasmus Microman on ITV from 1988 to 1989 and an appearance in Minder (S7E4: The Last Video Show, 1989).

His film work included Derek Jarman's The Tempest (1979), Breaking Glass (1980), Joshua Then and Now (1985), The Bride (1985), Chris Bernard's Letter to Brezhnev (1985), Peter Greenaway's A Zed and Two Noughts (1985), Charles Crichton's A Fish Called Wanda (1988), Hard Men (1996), Alice in Wonderland (1999), Saving Grace (2000) and Creep (2004).

Campbell's idiosyncratic presentation in Brainspotting, Reality On the Rocks and Six Experiments that Changed the World, each made for Channel 4, owed much to the influence of one of his heroes, the American Charles Fort.

From the late eighties onwards Campbell wrote and performed a series of one-man shows, each a mélange of autobiographical stand-up comedy, ontological speculation and popular-science rant.

If nothing else, the campaign had the effect of bringing to a wider public the Bislama for Prince Philip: Nambawan bigfala emi blong Misis Kwin ("Number one big fellow him belong Mrs Queen").

With Alan Moore, Bill Drummond, Mixmaster Morris and Coldcut, he appeared at the Royal Festival Hall in 2007 in a memorial tribute to Robert Anton Wilson, co-author of the Illuminatus!

He presented a series of literary improvisation shows, including a run at the Royal Court Theatre called Décor Without Production, in which the cast would create scenes and songs in the styles of poets, playwrights, novelists and songwriters.

One example of the extent to which Campbell pushed the actors was that by the end, each member of cast had developed four musical styles in which they could improvise, each corresponding to a different Elizabethan humour.

Campbell performed with 'The Showstoppers' in August 2008 in their second Edinburgh Fringe, reprising his School of Night role as on-stage director of proceedings in the final six shows of the run.

[19] Many contemporary performers cite Ken Campbell as an influence early in their careers, including Richard Herring, Nina Conti, Cariad Lloyd, Diane Morgan and Michael Brunström.