It has been claimed that the success of 'Fawlty Towers' was due to John Cleese's mental health troubles.

John Cleese

John Cleese

'Sherlock' writer Mark Gatiss, has claimed that John's much-lauded portrayal of cynical and snobbish hotelier Basil Fawlty and the mishaps that occur at his Torquay-based establishment was positively influenced by John being "mentally ill" at the time.

Speaking to Radio Times, he said: "Watch the first episode of 'Fawlty Towers' and John Cleese is so visibly mentally ill, he's got massive rings around his eyes and he's so sick and the whole show is infused with his manic anger and that's why it's so brilliant.

"Then Cleese got better and you can't deny that it's not as funny."

Cleese, 78, and his then-wife Connie Booth wrote all 12 episodes of the show and the comedian previously revealed that TV bosses had to be convinced that the comedy would be a success.

He said: "When we handed the first script in, the guy in charge of evaluating it wrote a memo that I have framed.

"It says, 'It is full of cliched situations and stereotypical characters and I cannot see it being anything other than a total disaster.'

"The show was good because we took six weeks to write every episode. Nobody takes that long now, most people take 10 days or a week. There was no temptation to do another series - we knew we would fail because we had set the bar too high."