Stepping up to the oche with the aim of spearing the cult of minor celebrity in its hollow Hello! heart, Irvine Welsh's Good Arrows took the fly-on-the-wall documentary and ripped the tail feathers off it. The saga of Andy 'The Arrows' Samson promised a cautionary sign of the times.

The timing was spot on. Darts is flying high so it was easy to swallow the idea of a small-town double-top hero seduced by a fleeting brush with fame. And Jonathan Owen was perfect as Andy, a beguiling mix of the innocent and the grasping, his ego buffed and fluffed to the catchy strains of Colin MacIntryre's should-be hit song You're A Star. As Andy suffered the slings and arrows of outraged misfortune, Owen actually made you feel sorry for him.

Set amid the disappearing world of working men's clubs in South Wales, Good Arrows could have made more of its bleak setting. But Welsh seemed to be going for broad comedy rather than sharp satire and some of the performances, notably Katy Brand as Andy's wife Big Stella, were comedy cliches that took a sledgehammer to subtlety. For all its notable ambition, Good Arrows never quite hit the bullseye.

It is, I confess, hard to imagine the Trainspotting novelist Irvine Welsh thriving at Cambridge but his absence from it might, you would think, be a boon when making a 'mockumentary' about the white working classes. Yet Good Arrows, which purportedly followed the decline of a former Welsh darts champion, was nasty and dreary. If the traditional sitcom is hard to make work so, post The Office and Borat, is the cod doc. When the best you can come up is inventing a drug fermented from faeces and urine and your lead actress apparently bases her performance on Nessa from Gavin and Stacey you cannot be surprised when ITV4 transmits its first original comedy commission at 11pm on a Saturday night.

Good Arrows, Dean Cavanagh and Irvine Welsh's pastiche documentary about a Welsh darts champion fallen on hard times, contained one very good performance, from Jonathan Owen as the "Beckham of Darts", and some nice lines. "What makes you think you'll get cancer, Andy?" asked the off-screen director at one point. "Well, cancer's very popular now, isn't it?" Andy replied witlessly. Unfortunately, there were too many performances that couldn't quite match it. As his mercenary wife, Big Sheila, Katy Brand treated every scene as a sketch, rolling her eyes and milking the gag in a way that completely disabled the attempt at low-key documentary realism. As a result, the dart hit the wires and bounced out.

The culture in Good Arrows is that of professional darts, with its beer bellies and working men's clubs, but colliding with the world of Heat magazine. This one-off mockumentary was co-written by Irvine Welsh - who surely was responsible for the bit with one of the foulest home-made drugs ever conceived, involving bodily waste - and based around a hapless filmmaker trying to profile Andy 'The Arrows' Samson, known as "the David Beckham of the darts world". Or at least according to his pushy wife and manager, insisting that they're plagued by paparazzi - or will be, any day now.

This was a broad satire, with easy targets like celebrity culture, darts players being thick, and the wife (Katy Brand) squeezing herself into inappropriate outfits. There were a few dark laughs, such as the charity stunt gone wrong when Samson tried to throw a dart into an apple on a boy's head, William Tell-style. But the joke ran its course in half an hour - yet there was another 90 minutes to go. There was simply no need for such length, but as Welsh also directed and produced, perhaps there was no one to rein him in.

This mockumentary about a darts player who loses his throwing skills after a heart attack marks Irvine Welsh's directorial debut on a feature. It's also ITV4's first comedy commission with Welsh offering.

Irvine Welsh makes his feature-film directorial debut in this dark comedy-drama set in the world of South Wales professional darts. Katy Brand and Jonathan Owen (of her own Big Ass Show and Shameless respectively) are the two stars and - as always with Welsh - this is an almost farcical, sometimes obscene production. But there's a point too: satirising minor celebrity, the drama focuses on a formerly great darts player (Owen) and his place in a society still ravaged by pit closures and social deprivation. The script takes pot shots at the standards of modern fly-on-the-wall documentaries, and there's a cameo from darts star Richie Burnett.

Irvine Welsh on Good Arrows

An interview with Irvine Welsh.

Irvine Welsh, the author of Trainspotting, turns his attention to the world of professional darts in a satire of what he calls "the most vacuous and self-defeating foible of our times - the cult of minor celebrity". It follows the disintegrating career of a gormless Welsh darts player and his appalling wife and manager (Jonathan Lewis Owen and Katy Brand), as seen through the lens of a film-maker (Joe McKinney). Welsh is famous for writing the blackest of black comedies, only here the comedy is broader and more exaggerated - more Star Stories than Trainspotting. There are flashes of bleak and shocking humour, but at two hours it feels like an overblown sketch.