By Caroline Briggs
BBC News entertainment reporter
It's been 30 years since the classic comedy Fawlty Towers was first broadcast on television.
Fawlty Towers' four main characters were the engine of the show
The antics of Basil Fawlty, his wife Sybil, hapless Spanish waiter Manuel and the ever-sensible Polly grabbed the imagination when it first went out on BBC Two on 19 September 1975.
Subsequent re-runs of Fawlty Towers have confirmed its position as one of the finest British sit-coms.
And while it continues to be in many people's top 10 lists, the origins of Torquay's hotelier from hell have also become stuff of television legend.
In 1971, John Cleese and some other members of Monty Python's Flying Circus stayed at a hotel in Devon, which was run by an ill-tempered manager.
Cleese was struck by the comedic irony of an angry and frustrated person running a hotel where a winning smile and a calm conduct are time-honoured traits.
So when the BBC asked Cleese to come up with a sitcom some years later, the irrepressible Basil Fawlty was born.
He wrote the series with his then-wife, Connie Booth.
"At the start, Connie wrote the Polly and Sybil roles, and she and I wrote Basil together," Cleese said in a recent interview.
"We used to ache with laughter and feel awful about the life we were giving him. "
While Cleese played the snobbish Basil, Booth took on the role of Polly and Andrew Sachs played Manuel.
Manuel was often the target of Basil's wrath, receiving punishment for mistakes he was usually unaware he had committed.
But it was the interplay between Basil and his formidable wife Sybil, played by Prunella Scales, that provided some of the most memorable scenes.
Scales described filming Fawlty Towers as "challenging".
"John, quite rightly, was extremely rigorous about learning the script, and if you didn't he could get quite cross, which was fair enough," Scales told the BBC News website.
"Each episode was done in a week so it was quite hard work but John and Connie were absolutely wonderful to work with.
"I had known Andrew Sachs since before I was married, so it was an excellent team."
Scales said she believed the secret of the show's longevity lay in the writing.
"John and Connie wrote 12 episodes about 12 things in hotel management that made them mad and very angry, and they wrote passionately," she said
"When you watch some old sitcoms, however charming they are, they have often lost speed over the years. The speed of Fawlty Towers has lasted the distance."
It is a view shared by Alison Graham, TV editor of Radio Times magazine and long-time Fawlty Towers fan.
"There were no wasted words in Fawlty Towers," she said.
"It is so well-written and has such a brilliant central character. It is a 'character-com' and not a 'sitcom'.
"Characters like Basil Fawlty simply endure."
Ms Graham compared the series to other popular modern-day comedies.
"Fawlty Towers could be set at any point in time, not just 30 years ago, in the same way that One Foot In The Grave or The Office could have been 30 years ago or just last week."
Such was the success of the first series, audience demand for more led to a second series four years later.
But Scales explained that it was not always clear to everyone how much of a hit Fawlty Towers would prove to be.
"I remember when we recorded the first episode," she said.
"It was a Sunday night and the BBC producer was striding up and down saying 'I don't know what John is thinking of'.
Manuel would shake with fear every time Basil was around
"But of course he did know, and it has been very successful."
And one of the other reasons for that success, many believe, is that Fawlty Towers burned brightly then went out with a bang.
After the second series Cleese called it a day, leaving just 12 episodes of the sitcom.
"I think if it had still been going on today then it would not be as special as it is," said Ms Graham.
"We didn't have time to get tired of it and it left people wanting more."
Basil's relationship with the ever-coiffured Sybil - whom he affectionately called a "little nest of vipers" - provided some of the most memorable interplay.
Scales said she had firm ideas about their dynamics as a couple.
"I think it was my idea that she (Sybil) should be less posh than he was.
Cleese wrote Fawlty Towers with his then wife Connie Booth
"I thought what she went for in him was his poshness, but that her parents had run a small boarding house and therefore knew about hotel management which he didn't.
"She was the professional one, but he had grander plans than hers.
"I don't remember ever talking to John about this, but my idea was that Basil had completed his National Service and, with his de-mob money, went out and met Sybil in a bar in Eastbourne or somewhere.
"He thought she was a glamorous barmaid, she thought he was posh, and it went from there."
And what would Basil be doing now, 30 years after Fawlty Towers first opened its doors?
"Still trying to run a hotel and getting it wrong," Cleese concluded.