'They think they're so important, don't they? They really think they've got their fingers on the pulse of the nation. There's her, swanning round the foreground like an overgrown waltzing denture commercial. And behind there's that cross-eyed baboon who farts around in front of a rubber plant and behind him there's those two nancy boys. I mean, these people are famous, for Christ's sake.'
Esther Rantzen, who has seen herself mocked by everyone from Benny Hill to Rory Bremner, believes this is fair game. 'Janet Brown does a wonderful me . . . That reaction is absolutely right because we've been up there for so long. Of course we should be sent up.'
Tomorrow evening, That's Life finally reaches the end of its 21- year run with a celebration of its choicest moments. But for every 'aaah' sighed at the passing of the programme, there will be a 'phew' at the realisation that the jaunty strains of the Hanwell Brass Band, which recorded the signature tune back in 1974, will never be heard again (barring repeats, of course).
The show grew out of the late Sixties series Braden's Week, a proto-That's Life in virtually every respect - from the chirpy accounts of consumer woe and High Street vox-pops to the newspaper misprints and nudge-nudge
humour of the presenters.
The decision to launch That's Life in 1973 was taken by Desmond Wilcox, the head of documentary features with whom Esther was having a relationship and later married. It pitched her very much alongside her co-presenters - George Layton, who as a comedy writer went on to script Robin's Nest and Don't Wait Up, and Bob Wellings, later a presenter on Nationwide.
The programme captured that phlegmatic, 'well you've got to laugh', essentially British approach to the world. But far from being a celebration of life in its entirety, the programme dwelt on the irritating detail - overpriced gas bills and petty bureaucracy. John Major was probably watching That's Life when he dreamt up the Citizen's Charter.
Unlike the charter, the show was an instant hit, its folksy mix of jokes and investigative reports a welcome antidote to the BBC's hitherto rather sombre, austere factual output. Tabloid television, in every sense.
By the following year she was holding court from a stool at the front with her 'boys' (as the newcomers Glyn Worsnip and Kieran Prendiville were chummily known) perched behind a desk at the back. Added sauce came from Cyril Fletcher, an elderly gent in a leather armchair, whose cross- eyes only added to his naughty seaside postcard delivery. Esther's wrap-up of some domestic disaster involving a dodgy washing machine would generally end with the word 'Cyril' (pronounced 'Cyreel') - his cue for an 'Odd Ode' or examples of people whose names combined hilariously with their job titles.
Although the line-up changed to include the likes of Chris Searle, Paul Heiney and even Mollie Sugden (minus blue rinse and her troublesome pussy), the format remained the same - both a testament to its enduring popularity and an explanation of its now stale and outdated look.
Beyond the frippery, however, the programme scored numerous major consumer campaign successes - it secured rear seat- belts in cars, safer surfaces in playgrounds and the introduction of a cooling-off period after signing credit agreements.
The story of Ben Hardwick, a two-year-old dying from liver disease, moved viewers to raise pounds 150,000 for a transplant. Its Childwatch in 1986 led to the setting up of ChildLine, a helpline for children suffering child abuse. This and Ms Rantzen's subsequent work for the charity played a leading role in taking the issue of child abuse to the top of the social agenda.
In more than 2,500 investigations over 21 years, That's Life lost just three libel actions, including one brought by a Harley Street slimming expert, who successfully sued the progamme for pounds 100,000 after it had wrongly accused him of profiteering.
In its peak Sunday-evening slot, the programme pulled in 16 million viewers and received 10,000 letters each week. But after being shunted backwards and forwards to Saturday, its ratings fell to about 8 million. Last spring, Alan Yentob, the new controller of BBC 1, called time - the show's cosy, slightly corny populism finally proving too much for the highbrow Birtists in control at the BBC.
In truth, of course, most of the programme's best elements had been copied and refined in shows like Watchdog (consumer affairs) and Blind Date (ritual humiliation of pensioners).
Michael Grade, chief executive of Channel 4 and a former controller of BBC 1, believes That's Life 'has become part of British television legend'.
Esther Rantzen is perforce rather more modest. 'It's difficult for me to analyse. I hope that, through it all, if people go back to their childhood memories of That's Life, we provided enough amusement and enough of value that even the most sour and snooty commentator (acknowledges) that it did earn its place on the screen.'