In 1958, François Truffaut was in Paris making The 400 Blows, a film about the disgrace of human indifference that was to launch the French new wave and change the face of cinema for all time. That same year, on the set of a hospital in Buckinghamshire, Charles Hawtrey and Kenneth Williams sat in pairs of cotton pyjamas calling Hattie Jacques “Matron”. At lunch, the cast and crew nipped to the canteen for a plate of something hot, then back to the set for the afternoon; home by six.

The film, Carry on Nurse, was to be the biggest British box-office hit of 1959, and the second in a series of 31 films featuring a roll-call of comedy geniuses who knew that no matter how good they were, how high their profiles or pushy their agents, they would never see their names above the words Carry On. The franchise was everything. It would never die. Fifty years later it still hasn't.

Richard Webber's book is a chronological trawl through the Carry On series covering everything from early successes like Carry on Sergeant, to classics like Carry on up the Khyber, through to the buttock-clenching flop Carry on Columbus, and ending with a nod towards the proposed Carry on London. Webber has interviewed the makers of the series and many of the peripheral actors, but since most of the big stars are dead - Hawtrey, Jacques, Williams, Joan Sims, Sid James - he has naturally fallen to using diary extracts and old interviews, which give the book an unshakeable air of musty grief, of things lost.

And make no mistake, the world that Webber conjures is lost. A world where you ditched plans for medical school only to land a job as assistant editor on Olivier's Hamlet (director Gerald Thomas). A world where being a member of the Carry On team was like going back to school after the hols, gathering at Pinewood twice a year and “meeting old chums and sharing all the jokes and gossip. We knew we had a few weeks of fun ahead” (Sims). Where nobody complained about the cold dressing rooms and all discreetly agreed to ignore Hawtrey's mother as she drunkenly rolled lavatory paper down corridors, choosing instead to tease Nora, the make-up girl, about “having it off” - a phrase she'd never heard before but vaguely suspected meant something saucy.

It took six weeks to make a Carry On, period. Studios were locked at lunch, and everyone would down tools at 5.30pm to ensure no bills for overtime. Larking around on set was encouraged but when the cry “Right chaps, be loyal!” went out, everyone fell into line. It's hard to imagine anything more cosy. Pity about the alcoholism, cottaging, suicide attempts, depression, exploitative wages and increasingly cynical scripts, but this is not that kind of book. Sure, the decline of the series is politely described, with its talk of a Dallas-style Carry On (starring the Screwing family) and the transcript of Sims reaching orgasm while sitting on a washing machine (Carry on Emmanuelle), but this is a compendium more concerned with dates and details - Khyber (1968) was shot in Snowdonia, Camping (1969) in an orchard at Pinewood, and so on. It is decent and assiduous. But it never dares to do what it absolutely ought: kick back and show some love.

I mean, just consider the very concept of Bungdit Din and the Burpas invading the Afghan hill town of Jacksi only to be scuppered by a Private Widdle. Or the effortless way that Carry on Camping, even now, seems to conjure with pin precision the very smell of a bad British summer: boiled egg and inner soles. Ah, the sight of Sid James in a scratchy polo neck perving over his real-life lover Barbara Windsor as she bounces healthily around tents with her sweet cellulite and untanned skin under a thatched cottage of bleached hair.

Then there's the sheer fizz of the scenes in Carry on Cleo in which complaining British slaves are sold at a market stall in Rome called Marcus et Spencius, or the moment Williams knocks on a window and declares “I am Julius Caesar, I represent the Roman Empire” and the housewife inside replies, “No thanks, not today” - this some 15 years before Monty Python's Life of Brian. The heartbreaking sight of Williams, in Carry on Nurse, called on to have a crush on a woman wearing a beat-poetry- fan beret. Or Hawtrey's utterly inimitable lack of guile, climbing out of a tent with a girl and saying, “She's just been showing me how to stick the pole up!” His smile so wide, his legs so thin, his specs so cheap they will never fit.

For this, you have to see the films. But go on - try renting one. I was actually laughed out of one video shop (quite a cheek considering the place was happily hawking Sex Lives of the Potato Men). A deep shame attends the Carry Ons. Because the one thing they teach us is that we can never be innocent again, and that hurts. And it's hard to accept that the films were never terribly good even when they were brilliant. That they had the air of the sausage factory about them and always made us feel slightly short-changed in some way. In brief: our most enduring films have been about getting nookie at all costs and the consolations of the biscuit tin. The French got Truffaut, we got Bisto. Bring it on.

In rude health
For all the seaside postcard brio and music-hall ribaldry of the Carry On films, it's the execrable punning that is hardest to forget. Kenneth Williams as Caesar, right, shouting "Infamy! Infamy! They've all got it in for me!" is deservedly famous, but Sid James in Carry On Cowboy (‘Once talked peace with the Sioux but you can't trust them. One moment it was peace on, the next peace off') is, admit it, irresistible, too.

Fifty Years of Carry On by Richard Webber
Century £18.99 Offer Price for Times Readers £17.09 Buy the book

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