THEATRE / Grim reaping: Alistair Fraser sees two modern Scottish novels take to the stage at Glasgow's Mayfest

Mayfest this year has adaptations of Joyce, Dostoyevsky, Marquez, Steinbeck, Gibran, Abramov . . . And it is not only the classics that are being reworked, but the work of contemporary novelists as well.

Trainspotting at the Citizens is adapted from Irvine Welsh's Booker-nominated novel about the lives of a group of heroin-addicted Edinburgh teenagers, it is a visceral, spare-you-nothing account of the lower depths of addiction.

Ian Brown's production moves effortlessly from the drug-induced highs to the drab, violent and often tragic lows. The language is heightened to a rapid-fire stream of invective as the characters zigzag across the underbelly of Edinburgh. Ewan Bremner's Mark is our guide to this netherworld; an angular, fidgety youth, nervous and loud by turns.

The teenagers' lives revolve around the ritual of 'cooking up' their heroin, and the endless search for 'scag'. The four main characters - Mark, Tommy (James Cunningham), the neophyte who comes to heroin when he loses his girlfriend, Alison (Susan Vidler), a young mother who loses her baby in a cot death, and Franco (Malcolm Shields), all smart suits and aggression - share a dilapidated flat, their only furniture stained mattresses. Gradually, their lives fall away from them; their friends become colleagues in the eternal trading for smack, and then the colleagues become corpses as the grim toll of overdose and Aids mounts.

Grim as the scenario is, the play also has enormous wit and humour. Marco's search for his opium suppositories, accidentally discharged during a bout of diarrhoea, makes you laugh, then makes you regret your laughter. It is a hugely potent piece of work, giving social issues a human perspective. These characters - played with great maturity by a young cast - are not the 'demonised' addicts of the popular imagination, they are humans in three dimensions, born into lives that give them little chance. The addiction ritualises their desperation. It also kills them.

Benchtours are a rapidly rising Scottish company who normally devise their own shows. For this year's Mayfest, however, they too have adapted a novel from a contemporary Scottish writer. The Bridge by Iain Banks is an exploration of the mind of the victim of a near-fatal car accident.

Directed by Jean-Federic Messier, this is Benchtours' most ambitious show to date. The dreamings of the coma victim are played out between four towers and the audience are invited to walk among the action, sharing his imaginings. The outside world is shown through gauze, on which are projected the scenes outside his mind.

The cast is very able, but appears to have difficulty in following the complex story. The opening scene takes place, without warning, in the bar of the theatre. The audience is then ushered into the main acting area, following the play as it moves.

Unfortunately, the basic storyline is established in those first few minutes and if you chose the wrong end of the bar it was lost. Once in the main area too much was played at floor level; all but the very tall lost the action. And the short couldn't get by by listening alone; the Fruitmarket is a wrought-iron and brick shell, and it echoes.

For those who could see and hear, however, this was a highly impressive production, matching Iain Banks' dark and surreal vision with Benchtours' own assured imagery and technical bravado.

'Trainspotting' at the Citizens Theatre, Glasgow, to 21 May, then at the Traverse Theatre, Edinburgh, 25 May- 19 June. 'The Bridge' is touring