The Arthurian legend has proved itself popular ever since 932 when this musical is set. At the top end of the market, Malory wrote Le Morte d'Arthur and T.H. White The Once and Future King, a novel that was successfully turned into the musical Camelot.
However, for many people of a certain age, the definitive Arthurian story is Monty Python and the Holy Grail. This remarkable cinematic homage to silliness has now been spun off into a musical, which rather against the odds has become one of the most successful on Broadway and now comes to the home of its progenitors.
Eric Idle, who has written the script, ensures that we never forget the original Pythons and frequently, as a line is spoken the picture of one of their number, especially John Cleese for some reason, comes to mind. It could be that he got himself an awful lot of the best lines.
Designer Tim Hatley keeps to the spirit of the original by lovingly recreating Terry Gilliam's cartoons on stage, most memorably with God's gigantic feet, which eventually propel themselves back to heaven with the aid of rockets.
Tim Curry, who created the role on Broadway, plays King Arthur (until January when Simon Russell Beale takes over) mixing lashings of wounded dignity with great comic timing.
After a dose of Finnish Fisch Schlapping, we get straight into the action. King Arthur appears on an invisible horse, coconut-clopping sound effects provided by David Birrell as his faithful, downtrodden servant Patsy.
The bad taste then moves into overdrive, as the Python crew tap straight into the main concerns of Britain's 10th century by exploring the comic possibilities of the plague. Talented West End debutant Darren Southworth plays Not Dead Fred who rises from a cartload of bodies to sing "I'm Not Dead Yet".
Arthur feels a need to fill his very very very round-table with gallant knights and so begins a search that yields the campest bunch imaginable. The team is inevitably led by Tom Goodman-Hill's Sir Lancelot, who, instead of debauching his king's wife, beds pretty Prince Herbert, a very different type of Queen.
They are joined by Cowardly Sir Robin (Robert Hands), flatulent Sir Bedevere (Tony Timberlake) and vain Sir Dennis Galahad, played by Christopher Sieber who has been specially imported from the Broadway production, more for his singing voice than dreadful English accent.
The quest for the golden vessel used at the Last Supper is more often funny than hair-raising, particularly when first the King and his knights are rebuffed by the insults of besieged Frenchmen and then they are set tricky tasks the Knights Who Say Ni. First they have to find a shrubbery and then put on a musical in the West End, with only 1,000 years to prepare and a shortage of the necessary ethnic mix.
By this stage of the two-and-a-quarter hour production, the Python aficionados or groupies are cheering ahead of the scenes and laughing before the jokes but for them the zenith is reached when Patsy launches not only the cast but a fair proportion of the audience in a jaunty rendition of "Always Look on the Bright Side of Life". It almost goes without saying that this is the stand-out song of the evening and to be honest, it is the only one that is likely to live in the memory.
The other musical high points are almost all provided by The Lady of the Lake, the impossibly tall and really rather terrifying Hannah Waddingham. She has a great time sending herself up and demonstrates tremendous vocal versatility much to the delight of the audience.
The send-up is Monty Python's great strength and this production, directed by Mike Nichols who is most famous for the film of The Graduate, is at its best when it deconstructs both the legend and the art form
With anachronistic allusions galore, particularly to other musicals; and some big production numbers which show off Casey Nicholaw's choreography to great effect, Spamalot should prove as big a crowd pleaser in London as it has in New York.
The jokes don't always hit home but a large proportion are extremely funny and with a large potential following who would kill any number of dead parrots to get in, a long run seems almost guaranteed.
One word of warning - if you are offered seat D1 in the stalls, even at a cut-price, run for your life. That is unless you have your dancing shoes on and want to make an unexpected fool of yourself onstage in a West End musical.