Previews are under way for what promises to be the "theatrical phenomenon" of the season, if not the year. Billy Elliot: the musical is the stage version of "one of the most adored British films of the last decade", as the publicity material puts it, with a score by Elton John and direction from its original helmer Stephen Daldry. Billy's arrival chimes with a resounding carillon of feel-good, watered-down, compilation and back-catalogue collections in London's West End, from Mamma Mia! to Mary Poppins via We Will Rock You - "Now in its Third Sensational Year!". Even in "straight" theatreland, the heart sinks as yet another Hollywood or American TV star jets into Shaftesbury Avenue hoping to Botox a wrinkly CV with a bit of serious board-treading.
Off the West End, things are a bit happier. Nobody could accuse the Donmar Warehouse's Days of Wine and Roses of being an easy ride. On the other side of town, at the Menier Chocolate Factory, Philip Ridley's Mercury Fur has stirred up a hornet's nest with its violent, dystopic view of modern youth. And at the Royal Court in Sloane Square, Alan Rickman will be directing a play on the life and death of the peace activist Rachel Corrie. If you want it, you can find theatre as catharsis, injunction and moral instruction. But not at the centre, in the commercial West End.
For one thing, shows are too costly and tickets too pricey. Who wants to fork out £40 or more (nearer £100 if you're not going alone, even if you skip supper) for a night at the theatre that is not guaranteed to be a success. Producers, mindful of the bottom line, are again and again opting to put on shows that major on recognition, name-tagging, the known. If celebrity sells, familiarity undoubtedly rules: the face you recognise from TV or film, the well-used storyline, the songs you've grown up with. Buying into a brand name makes economic sense, a short cut to the punter's wallet, as word of mouth takes time and producers don't have that luxury any more. So familiarity is the key. Familiarity - that underrated, oft-misinterpreted land to which we return, as we do to bed and sleep, when real life gets too much.
Only the very brave (Dame Ninette de Valois was one) voluntarily recognise constant change as the motor of creativity and life. For the rest of us, the sense of touching hands with some-thing already known produces a quite extraordinary endorphin surge, a kind of childish state of serenity in which we can relinquish the "adult" imperative to tussle with the unknown. For an hour or two, we can sit back and wallow in the certain knowledge of elements already encountered, signs and sounds already processed, with individual firewalls raised. We're OK, we're safe, and it feels - and maybe is - deliriously liberating, like taking a long warm soak in a specially prepared bath. No wonder a familiar song or well-known face proves so seductive, so irresistible.
Recently, there has been an additional factor. Since 9/11, the Iraq war and the Madrid bombings, fear and loathing have been fed into the body politic like a septic drip. In times of uncertainty, it becomes not so much a wish, but a prerequisite, to reach for entertainment as a comfort blanket: escapism as distraction.
This was certainly the case during the Depression in America. The stock-market crash ushered in the golden age of American musicals, all sequin sparkles and happy endings. In 1929, the Best Picture Oscar went to MGM's The Broadway Melody. In Britain the same year, Noel Coward's Bitter Sweet sent audiences out to the refrain of "I'll See You Again". But 42nd Street and Gold Diggers (both 1933), with their appeal to fantasy ("We're in the Money") and political awareness ("Remember My Forgotten Man"), were also products of this era.
The 1930s also brought the rise of the Federal Theatre Project - the only fully government-sponsored scheme ever in the United States - which was dedicated not only to finding jobs for unemployed theatre workers, but to making theatre that was politically, socially and regionally relevant. This proved that entertainment doesn't have to be a complete cop-out, set to the tub-thumping rhythm of the complete works of Queen.
And yet Billy Elliot arrives in a West End that is devoted to the cosy cushion of remembered pleasures. It will probably be a smash. As brands go, it's halfway there, familiar not only from the cinemas, but also courtesy of a peaktime screening on television over Christmas. It's already known to a vast public who love it and who, in a sense, have taken "possession" of it. They already feel Billy is a part of them, thanks to Lee Hall, who devised the story of aspirational triumph set against hideous political division and personal blight.
Even the subsidised sector, which is partially aimed at en- couraging innovative theatre, has fallen for the current vogue for comfort. Alan Bennett's The History Boys has been a box-office hit at the National Theatre this year, and has picked up every Best Play prize going. At root, it's a fanciful tale, with Bennett looking back with nostalgia to a 1950s world via the 1980s. His schoolboys, though, are no more products of the 1980s than they are the 1950s. It is a fantasy of how, maybe, Bennett would like school to have been, which gives him the licence to criticise the lack of real educational imagination today. It is full of acerbic one-liners, and offers marvellous roles to an ensemble of young men who grab their chance with both hands.
But, crucially, it also provides middle-class audiences - still theatre's majority stakeholders - with an evening of wholly familiar apercus, culled from a period whose idea of education as a "leading out" - a place of overall development of the child, not of brutal adherence to curriculum first, last and always - probably corresponds very much to their own. Presented with humour, sympathy and compassion, it is no matter that Bennett's play skates over the vexed question of paedophilia. Perhaps because he makes such light of it and presents boys so at ease with themselves, confident enough to laugh it off, Bennett has anticipated a current zeitgeist of uncertain national identity. These are our values, he is saying, this is how we like to think of ourselves - tolerant, liberal-ish, passionate about words and the life of the mind. But about problems, questions, issues, the answer at the moment is more unsure.
Is the comfort-blanket package a seductive one? I'll say. Wish fulfilment, reassurance and happy endings will always win out over besmirched, unforgiving, relentless reality, or the shock of the new. That's why The History Boys has swept all before it, why Billy Elliot: the musical will have them hanging from the rafters, and why well-upholstered, expensive-looking retreads will always have a place in people's hearts, when those hearts are looking to be nurtured.
Carole Woddis is a theatre critic