It wouldn't be overstating things to say that the songs sung by Gene Wilder's Willy Wonka and the rest have gone beyond being merely well-loved and into the realms of folk memory in many households. Mendes's new West End production not only survives comparison - despite openly inviting it on several occasions - but stands proudly on its own feet as a remarkable piece of work.
You know the story. Pauper Charlie Bucket loves chocolate but just gets a bar a year on his birthday. Chocolatier recluse Willy Wonka has a contest to visit his factory and get a lifetime supply. Five golden tickets. Five kids. One ridiculous, magnificent, incredible, terrifying, awesome day out.
The author apparently thought the first film version of his story had too much Wonka and not enough Charlie, but - sweet though he is - it's inevitable that a good boy called Bucket is a bit wet. While Nigel Planer's eternally young Grandpa Joe is the heart and the audience's way in, Wonka is the dizzying enigma at the centre. Douglas Hodge absorbs Dahl, Wilder, Depp, Barnum and the Wizard of Oz for his old school reading.
Where any musical really stands and falls is the songs, and while Marc Shaiman and Scott Wittman are perhaps a little too firmly stuck in the classic Broadway mould and don't hit the mark with every number, they do just about enough to rub shoulders with the class of '71.
It looks astounding, though the first half slightly less so. The stage set for Charlie Bucket's home is a bit more ramshackle than shack, but the TV broadcasts of the other golden ticket holders is a very special bit of staging and, in Augustus and Veruca in particular, introduces the most fun characters of the whole production.
The second half is simply eye-popping. The four not-so-lovely children's uppance is come in a series of remarkable set pieces that would put the makers of Final Destination to shame. To say too much would be to give away the surprise, but there are pipes, animatronic squirrels, gum 'n' glitter and the most imaginative people-puppet Oompa Loompas ever realised. We're saying nothing about how they do the Mike Teavee bit on stage. It's all so vivid you can taste it.
In the final moments writer David Greig takes two ridiculous, brilliant decisions. The moral focus of the whole piece is shook up with a teeny, tiny, vital story tweak (redemption comes not for loyalty, but for the gift of pure imagination) and the debt to Gene Wilder is paid in full. It's a testament to how much goodwill he's earned and how well he executes the scenes that he gets away with both.
For grown-ups? Kids? Some references will go over the heads of the youngest members of the audience (Lady Chatterley's Lover) and the older folks will probably get a headache from Mike Teavee's appearance as a Billie Joe Armstrong-alike gamehead, but from Quentin Blake's inimitable opening animations to the great glass elevator, both will likely be won over by the visual feast.