A semi-autobiographical tale of the making of a typical x-rated film from exploitation veteran Michael Armstrong (made at the behest of Stanley Long), Eskimo Nell stands head and shoulders over its tit-’n'-bum cousins. Film-school graduate Dennis Morrison (Armstrong) seeks directorial work in Soho, but the only person who’ll have him is shabby tit film producer Benny U Murdoch of B.U.M. Productions (Roy Kinnear). Finding his lofty ambitions to arthouse profundity undercut by Murdoch’s insistence on lashings of norks, Morrison hooks up with producer Clive Potter and virginal, penguin-obsessed scriptwriter Harris Tweedle (Christopher Timothy) to produce a cinematic version of the infamous dirty poem, using money derived from three different backers, who, inevitably all have their own designs on the finished film.

Cigar-chewing Yank impresario Big Dick pushes for a hardcore film starring the singular talents of his ditzy bit on the side, Billie Harris (a self-styled cross between Brigitte Bardot, Marilyn Monroe and Peggy Ashcroft). Wealthy banker Ambrose Cream (‘Through my investment company Cream Holdings, I’ve been able to give many young people a helping hand’) wants a Sound of Music knock-off tailored to the strengths of his opera-singing, karate-chopping protégé Millicent Bindle. Vernon Peabody, meanwhile, offers cash for the first all-British gay western, with young companion Johnny in drag as Nell. While Tweedle busily types out three different scripts, Murdoch legs it out of the country with the cash, with the hapless trio left legally obliged to satisfy the backers. Morrison’s girlfriend (a husky-voiced Katy ‘Dr Who’ Manning) suggests tapping her mother Lady Longhorn, a Whitehouse-alike moral crusader, for the cash. She, however, is under the impression this is to be a family film, and thus a fourth version is born, starring Manning and Longhorn’s drippy son (Christopher Biggins). Somehow, all four films get made, on the same set, with actors from each version bustled in and out in shifts. Morrison spouts flowery nonsense to the actors (‘You symbolise the dialectical collection of opposites coming to a listless, distanced unreality’) while the various Nells behave with diva-ish arrogance, and genitalia are inevitably caught in clapperboards. And to cap it all off, there’s the time-honoured comedy chase to stop the dirty version being accidentally screened to Her Majesty at Leicester Square.

Despite an ending shamelessly swiped from The Producers, Armstrong’s script is uniquely sharp among sexcoms. He nails various figures in the business (Murdoch is a very thinly-veiled version of Tigon supremo Tony Tenser). The squalid absurdities of Wardour Street’s operations are captured with a gimlet eye. Best of all, the dialogue pushes the usual sexcom string of ‘big one’ single entendres into a non-stop flow of off-colour puns and filthy Spoonerisms (‘I see fur clad figures, set against vast panoramas of whining shite…’), coming thick and fast (‘almost Joycean’ as Morrison would no doubt muse). It’s the smartest sex script on the block, but one which still appreciates the comedy value of a well-timed ‘Oh, bollocks!’