Had Mary Whitehouse not existed, it would have been necessary to invent her.

The Sixties were swinging and letters signed “Disgusted of Tun-bridge Wells” went unanswered by the permissive executives at the BBC. Who could stem this rising tide of filth? Step forward an indomitable housewife-superstar from Wolver-hampton, She Who Must Be Dismayed. Her clean-up crusade brought down the BBC’s Director-General and terrified liberals in the Church, the state and the stage. It has taken the BBC eight years since her death to dare mine the comic potential of her life as the self-appointed leader of the “moral majority”.

The Mary Whitehouse I knew was a tough, feisty, vainglorious woman, in league with the right-wing moral rearmament movement, instinctively aware of her opponents’ weaknesses and unscrupulous in exploiting them.

However, in all her autobiographies (she wrote three), she created the myth of the humble, self-effacing teacher, chosen by God to lead the country out of the moral wilderness cultivated by clever liberals. She was David, who dared to take on the Goliath at Broadcasting House, slaying him, not with pebbles, but with postbags of complaints by her legion of followers, who sat glued to BBC Two solemnly recording every swearword in the Play for Today and every innuendo in Pinkie and Perky.

The dramatist Amanda Coe has taken her at face value and run with her own account of the humble housewife who has greatness thrust upon her. It is a richly comic story and Mary is robustly reincarnated by Julie Walters, upstaged every few minutes by Alun Armstrong as Ernest, her bewildered postman husband, who alerts her to the acronymic danger of her original name for her campaigning organisation, “Clean Up National Television”.

To make the production work, Mary’s enemies must be made equally ridiculous. So, Sir Hugh Carleton Greene is reinvented as a manic John Cleese figure, a lecherous, upper-class, overclever twit brought down by the simple soul he is too stuck-up to meet. Hugh Bonneville does a fine imitation. And there is a wonderful (and more accurate) portrayal of Lord Hill, the smarmy “radio doctor” who ran ITV and disarmed Mary with tea and cakes. But it was Harold Wilson, not Mrs Whitehouse, who really engineered Sir Hugh’s removal by making the pliant Hill chairman of the BBC. It was Greene’s penchant for satirising politicians and not his support for Play for Today that was his undoing.

The television play ends by showing how Mary learns to manipulate the media – a formidable talent she had from the outset. It swallows her pretence that she was not interested in politics, but, on the contrary, despite the laughable obsession of her followers with sexual innuendo, her true concern was with liberal and left-wing ideology. Her early target was Cathy Come Home – Ken Loach’s drama about the underclass – and she discerned psychological discord and social anarchy in every Dennis Potter play.

Her fear of homosexuals was visceral. She claimed that homosexuality was caused by abnormal parental sex “during pregnancy or just after”. Being gay was like having acne: “Psychiatric literature proves that 60 per cent of homosexuals who go for treatment get completely cured.” It was with this sort of nonsense (in her first book, Whatever Happened to Sex?) that she was ushered into the Establishment in the 1970s and permitted to pray in the Old Bailey corridors for the conviction of Gay News.

Her real political agenda came to the fore in her alliance with Mrs Thatcher, whom she supported at every election. This was a betrayal of her cause at the time that it could have meshed with the antiporn feminists in the Labour Party. It was under free enterprise Thatcherism that sexual profiteering began to thrive in the Eighties – from the groaning “adult” shelves of every corner newsagent to the dirty talk on telephone lines leased from the newly privatised British Telecom.

Mary’s bandwagon was finally derailed when her prosecution of the National Theatre for staging The Romans in Britain(Howard Brenton’s play attacking British Army actions in Northern Ireland) collapsed. She had privately prosecuted the play’s director, but had been too mean to pay for her solicitor witness to occupy the best seat in the stalls, forcing him to sit at the back of the Olivier Theatre. From this vantage point, he could not say for certain whether the object that touched the naked buttocks of Greg Hicks (playing a druid priest) was the tip of a centurion’s penis or the tip of a centurion’s thumb. After the case was thrown out and she had been ordered to pay costs, she cut a doleful figure, muttering tearfully that “God will provide”.

Filth is an enjoyable play and serves as an amusing reminder of that age when the phrase, “You’ve got to admit Mrs Whitehouse is right about some things”, briefly entered the language. Her only achievement that lasted into the 21st century was the Broadcasting Standards Council. But its motto, “television: a guest in the home”, became obsolete with multichannel choice and it was finally replaced by Ofcom, which gave BBC Two its belated revenge by approving the screening of Jerry Springer: The Opera.

Nonetheless, Mary’s cultural vandalism left its mark, curbing the most creative period in British TV drama. If the corporation ever wishes to pay her a genuinely backhanded compliment, it should run a Mary Whitehouse season, devoted to all the comedy, drama and current affairs programmes condemned by her National Viewers’and Listeners’ Association. It would provide more entertaining and enriching television than its current output.

Filth: The Mary Whitehouse Story, Wed May 28 2008, BBC Two, 9pm

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