Sam Bain

When I interviewed Peep Show's Jesse Armstrong a couple of years ago, I asked him whether he and co-writer Sam Bain had thought about quitting while they were ahead. "It takes self-awareness to know when you're past your peak ... we'll probably lack that like everyone else and crank them out until [audiences] are bored of them," he joked. But though the ever-increasing profile of its stars David Mitchell and Robert Webb would suggest there's no danger of audiences getting bored with this caustic flatshare sitcom anytime soon, I do wonder whether the new run would do well to be the last.

The problem, to this carping critic at least, is that where its original brilliance derived from the stasis of its lead duo, thirtysomething suburban odd couple Mark and Jez, they have increasingly fallen prey to such conventional dramatic demands as plot and character development. In Friday's hospital-set series opener, indeed, we saw Mark become a dad, a game changer which resulted in an ending of disorientating sentimentality. That's not to say that Peep Show isn't still a lot funnier than most of the competition; only that these are two self-destructive Peter Pans who should never be allowed to grow up.

Is Mark Corrigan ready for fatherhood? Of course not - but he doesn't really have much choice in the matter.

As series seven opens, Sophie is on all fours in the delivery suite, screaming out for gas and air, a water birth, an epidural and, ideally, a less useless birthing partner.

There's every chance the baby will be an adult itself before Mark is grown up enough to deal with a responsibility like this - so there's no surprise tonight when he deals with the stress by hiding.

For self-obsessed man-child Jeremy, the hospital provides an unexpected opportunity for him to get over his ex when he meets another girl visiting her ­coma-stricken boyfriend.

That's just one of the many reasons to love Jeremy - he could be falling headfirst down an active volcano and his number one impulse would still be to scour the area for talent.

As a new arrival ushers in a whole new arena in which Mark and Jez can fail to shine, perhaps this will finally be the series when the nation discovers how to press the number 4 on their TVs, Peep Show makes the long overdue leap from cult hit to national treasure and David Mitchell, Robert Webb, writers Sam Bain and Jesse Armstrong and director Becky Martin are carried around the streets of London on golden sedan chairs. We can but dream.

Writers: "There's a bit of Jez and Mark in everybody"

"This could be another way to save money on the budget," chuckles Jesse Armstrong as he dangles one of ShortList's handmade Mitchell & Webb marionettes for our photographer. He's kidding (we think), but if he and his writing partner Sam Bain did decide to turn Peep Show into a crude puppetry programme, they probably could. And we'd probably watch. They may not be as ubiquitous as the show's stars but creators Armstrong (sharp jacket, booming laugh) and Bain (glasses, dry one-liners) are the brains and heart of Britain's funniest sitcom. And they've got an embarrassing tale or two themselves...

Despite never attracting the wider audience it deserves, Peep Show - starring David Mitchell and Robert Webb as Mark and Jez, a latter-day flat-sharing odd couple - has from the outset maintained its reputation as one of the very best British sitcoms. Now entering its seventh season, it is also Channel 4's longest running comedy and, happily, shows no signs of falling off in quality. Quite the opposite; tonight's episode opens up a whole new vista of comic possibilities as Mark (Mitchell) marches none-too-enthusiastically across the Rubicon that is parenthood and, initially at least, doesn't respond well to the prospect of responsibility.

Jesse Armstrong and Sam Bain's scalpel-sharp script brilliantly exposes the average male's helplessness, incomprehension and terror when confronted with the maternal agonies of childbirth - and the overwhelming urge to run away. Meanwhile, in a different wing of the hospital, Jez (Webb) seeks a cure for his recently broken heart in the shape of the attractively bookish partner of a comatose patient - with predictably cringe-making results.

Jez and Mark ... by the people who know them best

As they return for a seventh series, will fatherhood make men of the El Dude brothers? Who better to ask than writers Sam Bain and Jesse Armstrong and stars David Mitchell and Robert Webb?

Sam Bain and Jesse Armstrong Interview

It is said that the secret of good writing is to write about what you know. As such, you might expect the writers of Channel 4's Peep Show (which is definitely good writing) to be two miserable, socially inept losers holed up in a rather depressing flat, bickering relentlessly. It's something of a surprise, then, to find that they are a cheerful, seemingly well-adjusted duo, who work from of a Thameside office with glorious views to the Palace of Westminster.

Written by Peep Show creators Sam Bain and Jesse Armstrong, with assistance from Simon Blackwell, The Old Guys is a reasonably successful attempt at fitting their "edgy" comic sensibilities - they also contribute to The Thick of It - within a more traditional mainstream framework.

Amusing, lively and nicely performed, this comedy about mismatched OAPs, played by sitcom stalwarts Roger Lloyd-Pack and Clive Swift, has improved since its first series.

Lloyd-Pack in particular looks far more comfortable, and hogs all the best lines as a feckless old hippie.

While the similarities to Peep Show, in terms of dialogue and characterisation, are still distracting, The Old Guys has an agreeable charm of its own. Ignore the woeful My Family which goes out before it: the mainstream sitcom is far from dead.

The sitcom shuffles into a second series but if you're coming at it new, prepare yourself for a world that's a lot less subtle than that more famous creation from writers Sam Bain and Jesse Armstrong, Peep Show. The flaw this opener shows up is that the dialogue doesn't seem to sit right coming out of the mouths of the show's aged housemates. Still, we're in the safe hands of comic veterans Roger Lloyd Pack and Clive Swift of Keeping Up Appearances.

Moved to a new home on Friday nights, where it's much-needed, the second series of The Old Guys feels as comfortable as a pair of slippers.

Ironically, the first series suffered from the fact that it was created by Sam Bain and Jesse Armstrong. Their fans would have been expecting Peep Show for pensioners - and it certainly wasn't that.

It was more like Men Behaving Badly meets One Foot In The Grave. Its sense of humour might be cutting but it could never be described as cutting-edge, and it wasn't trying to be. It was safe, cosy and non-threatening - aimed firmly at the kind of viewers who loved Clive Swift as Hyacinth's husband in Keeping Up Appearances.

Series two finds Swift and Roger Lloyd Pack's flat-sharing Old Couple still lusting after their sexy but oblivious neighbour Sally (Jane Asher) and dismayed that she's found "another bloody boyfriend who isn't us". But there's a new woman on the scene - a librarian, played (improbable as it sounds) by Cherie Lunghi. You can already start to see Jane Asher's glamorous hackles rise and having a bit of competition (even for two men she's not remotely interested in) should put the cat among the pigeons.

This week Tom and Roy enter a pub quiz to prove that age hasn't shrunk their brain cells. And Tom's quest continues to underline how even though they might both be old, he's not as old as Roy. "You did National Service in Caterham," he points out. "I did acid in Wardour Street."

It may be Pensioners Behaving Badly, but I found the first series of this comedy from the writers behind Peep Show (predominantly Sam Bain and Jesse Armstrong, with this first episode written by Simon Blackwell) more enjoyable than the concept would indicate. Roger Lloyd Pack and Clive Swift bicker about everything, not least their mutual attraction to neighbour Sally (Jane Asher).