Fawlty Towers was borne not of the wild and inventive imaginations of its writers, John Cleese and Connie Booth, but of a real experience at a real hotel with a real man.

The establishment in question was the Torbay Gleneagles Hotel, managed by proprietor Donald Sinclair. It was Tuesday 12th May 1970, and Cleese had checked in with the rest of the Monty Python's Flying Circus team in order to commence location filming for that programme's second series.

Sinclair (pictured with his wife), a man who Cleese later described as "the most marvellously rude man I've ever met", would reportedly berate his guests at almost any opportunity. On one occasion, Eric Idle's briefcase was thrown over a wall due to a "bomb scare" involving disgruntled ex-staff, and on another Terry Gilliam was berated for not using a knife and fork in the correct English manner.

Eventually, the rest of the Python team moved out to the nearby Imperial Hotel, but Cleese, fascinated by Sinclair's conduct and personality, stayed on, even inviting his then wife, actress and Python bit-parter Connie Booth, to join him. Together they continued to observe the hotelier's bizarre antics.

A little over a year later, on Sunday 30th May 1971, the transformation between Donald Sinclair and Basil Fawlty began. Cleese was one of a number of writers contributing to ITV's popular Doctor series, a spin-off from the Doctor In The House film and novel franchise. He had penned Episode 14 of Doctor At Large, entitled No Ill Feeling!. The character that Cleese would make his own, here known as Mr Clifford, was played by Timothy Bateson, and his description is a familiar one to any Fawlty Towers fan: a rude, incompetent manager of a small hotel, domineered by his wife and endlessly aggravated by his customers. It was more than 4 years until the world would be introduced to Basil Fawlty, but the seeds were being sown.

'A Touch Of Class', the first episode of Fawlty Towers, eventually made its debut on the BBC on Friday 19th September 1975 at 9pm.

The rest is more or less history, and a very common one for popular sitcoms: although it quickly gained a large following from the public (and indeed, Series 1 enjoyed a full repeat run as soon as it had finished), critical reception for the series was lukewarm, and internal BBC memos released in recent years have revealed that the series was nearly never made at all.

Series 2, like many other programmes of the era, was beset by industrial action. A strike caused the production and broadcast of Episode 5 to be postponed, and further strikes meant that Episode 6, Basil The Rat, was not seen until almost 7 months after its originally scheduled broadcast date (it eventually aired on Thursday 25th October 1979, at the end of a repeat run of the series). This was somewhat of a blessing, however, as a strike at ITV at that time left Britons with only the two BBC channels to choose from, ensuring high viewing figures.

Almost ever since that final episode was broadcast, rumours have persisted of a 13th programme, recorded but never transmitted. Whilst some of the speculation surrounding this episode is certainly persuasive, there is no reliable evidence that the said rumours are true, and in fact many clues to suggest that they are not.

For starters, the BBC is not in the habit of producing whole episodes of programmes only to allow them to lie in a vault somewhere. Particularly given its unique funding, it is highly unlikely that the corporation would not want to capitalise on such a programme: another episode's repeat fees, overseas sales profits, script rights, and DVD sales would be too tantalising an opportunity to miss out on. Further, given that the average sitcom studio audience comprises of somewhere between three and four hundred people - not to mention a few dozen members of cast and crew - any notion that the plot would not have 'leaked' over the past decades is, frankly, laughable.

Rumours of that episode have, however, no doubt partly been fuelled by John Cleese's own admission that he had developed the idea of a Fawlty Towers film during the 1990s. The project would see Basil and Sybil, now retired, flying to Spain to visit Manuel and his family. After lengthy delays at the airport, the aeroplane would be highjacked by terrorists: Basil, already irate after the delays, would have overpowered them and resumed control of the plane - before turning highjacker himself, insisting that the pilots continued to Spain despite being (understandably) ordered to return to London. In Barcelona, Basil would be arrested for his unwitting highjack, and only released just in time to join Sybil on the flight home.

It sounds an enticing plot and situation to see our beloved characters in, but - perhaps for the best - the idea never got past that basic storyline, and it is not believed that a word of draft script was ever written. The closest to a resurrection of the series came with GOLD's 2009 cast-reuniting documentary Fawlty Towers: Re-Opened.

However, it is possible there is a little bit of Fawlty Towers you may not have seen yet. John Cleese recorded the below introduction for an episode of Not The Nine O'Clock News in character as Basil Fawlty, but it was never actually broadcast.

As for Fawlty Towers itself, the building playing the part of the epnoymous hotel was Wooburn Grange Country Club near Bourne End in Buckinghamshire. During the 1980s the building underwent a series of ownership changes as the fortunes of the club - and venue - dwindled, eventually becoming a nightclub called Basil's. Finally, in March 1991, fire ravaged the structure, raising it almost entirely to the ground. The fire is widely believed to have been an insurance scam organised by the owners in tough economic times, but nothing was ever proven. A small housing development now stands on the site.

Meanwhile, Donald Sinclair's Gleneagles Hotel was knocked down in March 2016 to make way for retirement flats.

It may not quite be the real thing, but a fan of the sitcom has created a Lego version of the foyer

Basil lives on too. He was last seen in January 2016 thrashing a car in a Specsavers advert:

Meanwhile Australian audiences are now enjoying Fawlty Towers Live, the first official stage adaptation overseen by John Cleese. In the below video, John Cleese meets the new Basil, Stephen Hall: