The last ooh-err

Earlier this year the late Pat Coombs recorded her final radio sitcom after nearly 50 years in the business. We will not see her like again, says Matthew Sweet, who was there to watch

Pat Coombs is speeding dangerously along a narrow mountain road, burning rubber and cackling maniacally. In the boot she's stowed some suitcases belonging to June Whitfield and Roy Hudd, who, at the same moment, are being forced to bungee jump from the side of a mountain. Their elastic twangs alarmingly but, as this all takes place in a radio studio, insurance is no problem. Hudd and Whitfield are wailing in terror, barrelling backwards and forwards on the stage, carefully turning pages of their scripts. Coombs is smiling beatifically from her wheelchair, her big specs glinting under the lights.

This episode of Mike Coleman's sit-com Like They've Never Been Gone will be broadcast on Radio 4 later this month, but Pat Coombs will not be around to hear it. A fortnight ago, she died of emphysema, aged 75, and with her passed a certain kind of British comic figure, and a certain kind of British comedy. Her lanky body, that beaky nose, those Cruikshank features that always seemed to be on the point of hysterical tears or vengeful laughter, made her a fixture of TV comedy for several decades. But it was on radio that she was happiest, and her voice, like the noise of somebody trying to sandpaper a housebrick is, somehow, the sound of another age – an age when all sitcoms featured Cockney chars with knotted headscarves and catchphrases like "Can I do you now, sir?"

It's appropriate then, that her final radio appearance should be so sturdy and traditional a vehicle. Like They've Never Been Gone could hardly be said to be freeboarding on the spume of the zeitgeist. Indeed, there are some at Radio 4 who mutter that its natural home might be two networks below. Since 1998, however, Mike Coleman has been piloting his characters through four successful series of increasingly ludicrous plotlines. This is the premise: Hudd and Whitfield play Tommy and Sheila Parr, a forgotten Eurovision act whose personal obnoxiousness fails, mysteriously, to undermine the loyalty of their monstrously overworked domestic, Hetty (Coombs), and their son and agent, Murray (the magnificent Julian Eardley). Murray nurtures his mother's fantasy that she's still an international superstar; Tommy, who knows that they're in the doldrums of the D-list, pursues more venal interests; Hetty carries all the bags and has a knack of making the word "modom" sound like a savage insult.

A working day in BBC radio comedy remains almost unchanged since Coombs was playing stooge to Jimmy Edwards and Arthur Askey in the 1950s – except that most shows are now recorded, not broadcast live, and their casts are not required to wear evening dress. (Even the comic skivvies like Irene Handl, Dorothy Summers and Coombs herself did their act in their posh frocks.) Live shows tested the nerves. Directors would hand down notes and cuts during the performance, to prevent the show over-running. Roy Hudd recalls an edition of Workers' Playtime on which the star comic failed to coax a single laugh from the audience – it was made up of Polish sailors recruited from the docks and unable to understand a word of English.

Even so, he, Whitfield and Coombs are nostalgic for these ancient terrors. "The BBC would never let you do it now," reflects Whitfield. "They'd be afraid of what you might say." Hudd agrees: "They think that you'd say the word 'balls' and they wouldn't be able to do anything about it." "I think," chips in Whitfield, sweetly, "that it'd be rather old-fashioned now just to say 'balls'." Everybody waits with baited breath for her to produce a filthier alternative, but it doesn't arrive.

The cast's day begins at 4pm, when they assemble in the rehearsal room (the bar of the Drill Hall in Bloomsbury, while the decorators are in at the BBC Radio Theatre) and the programme's producer, Steve Doherty, oversees a read-through of the script. Coombs is the last to arrive. She glides into the room like a Georgian State dancer. Between her long fingers smoulders one of those skinny cigarettes that used to be advertised on the back of Woman and Home. She is more of a surprise than Whitfield and Hudd. The London Academy of Music and Dramatic Art (where she was a contemporary of Diana Dors) has smoothed and deepened the Camberwell vowels of her childhood to something more appropriately actorly. But as soon as she is called upon to deliver a line – particularly one containing the expression "ooh-err" – the familiar transpontine rasp returns.

After some minor adjustments have been made to the dialogue, the action transfers to the miked stage of the Drill Hall. Here, sound effects operator Jill Abrams sits, stage right, in front of a small table laden with objects: a little pot of bicarbonate of soda, a wine glass, a pop gun, some cutlery, an aluminium pan and a small wooden cupboard. Next to the three stars of the show, this piece of woodwork is one of the most celebrated relics of BBC Light Entertainment. Its hinges and tumblers have provided the sound of opening and closing doors in most radio shows since the war. Today, Abrams is using the prop to furnish the movements of doors in a ramshackle hotel in which the characters are forced to spend the night.

After the run-through, the cast retires to the dressing rooms of the theatre for sandwiches, white wine, and a gentle shove down memory lane. "Radio's all I ever wanted to do," says Coombs. "I never wanted to be seen, ever. I looked at myself in the mirror at the age of seven, stuck my tongue out and thought, you're a plain, ugly little madam. And I thought, voices yes, faces no. Who would want to see it? I didn't want to go on television, but it happened anyway."

Once she had shown her face on the box, it became one of the most instantly recognisable in the medium. She was the eternal foil: a meek, twittery character who occasionally managed to turn the tables on her bullies. Dick Emery, Reg Varney, Terry Scott and Bob Monkhouse were regular sparring partners, but she found her most enduring collaborator in Peggy Mount. Once they had starred in a 1971 sitcom entitled Lollypop Loves Mr Mole, they began to be regarded as a double act. In You're Only Young Twice, for instance, they were cast as Cissie and Flora, two cranky residents of a genteel retirement home. Mount was bullish and irascible, Coombs diffident and submissive. And their real-life relationship, it seems, reflected some of these qualities – particularly when they both moved into the same residential care home, where Mount died last November. "Love-hate" is how June Whitfield describes their relationship.

By this time, the audience is beginning to fill the auditorium at the Drill Hall. They're worth a note: most people are familiar with the habits and appearances of Trekkies and Hell's Angels, but the radio comedy studio audience is a relatively uninvestigated subculture. The same people come back night after night, addicted to the BBC ticket unit's endless something-for-nothing spree. They know what's required of them, and play their part with as much gusto as the performers. The hardcore have cultivated eccentric laughs – a basso profundo roar, a helium-squeaky chitter – so that they can identify themselves when they're listening to the broadcast programme in the bath.

When Coombs scoots on to the stage in her wheelchair, the room thunders with affectionate applause. She's like some maharaja in a howdah, making gracious headway across the room, absorbing the audience's enthusiasm. As the recording progresses, she and Hudd display a clever strategy for persuading the audience to laugh at the jokes in the script – they laugh at them all themselves. A gag that might have raised only an inaudible smile is lifted to a titter by an impeccably-timed (and equally inaudible) smirk in the direction of the audience. A pay-off that might have only garnered a respectable chuckle is amplified to a guffaw by some silent hysteria. Coombs prefers to shake her head in disbelief, Hudd to gurn into the crowd, but the effect is much the same. They are masters at work.

Once the show is taped, and retakes negotiated, I observe a group of pale young men, all clutching carrier bags, lingering by the door to the auditorium. They're waiting for a chance to speak to Pat and June. Whitfield emerges first. They cluster around her, but they don't want to have their photographs taken with her, or get her signature on a Like They've Never Been Gone publicity still (all obtained, presumably, long ago). They just stand very close, breathing in her perfume. It doesn't look like one of perks of the job. Then Coombs sails through the bar, beaming happily. The series is over, and the cast and production team are booked into an Italian restaurant off the Tottenham Court Road, where the staff will treat the veterans of Like They've Never Been Gone with papal deference.

The three fanboys watch her stately progress with awe. It's good that they're here to see it. This is the final exit of Pat Coombs. The last ooh-err has sounded.

A new six-part series of 'Like They've Never Been Gone' begins on BBC Radio 4 on 19 June at 11.30am