"Bully beef" is a type of canned meat: flesh encased in metal. So there's grim humour in the title of this newly-written play, set inside a prototype British tank stranded between the front lines of the First World War. The crew, trapped inside, can't leave their iron prison; but the German army sense the chance to commandeer this frightening new war-machine, and daren't risk deploying heavy fire. The stage is set for a deadly stand-off, where the nature of duty is hotly debated, and passions both inside and outside the tank run high.

With so many hours of stage time already dedicated to the First World War, it's no small achievement to find new angles to explore. But playwright Peter Garinder largely succeeds; partly thanks to the novel setting, but mostly because of the dynamics he builds between the stranded crew. Three of the men know each other from school – a modestly posh school by the sounds of it, perhaps a county-town grammar. The fourth, a much older man, is a veteran of the Boer War some twenty-five years before, and naturally has a different perspective to his wider-eyed young peers.

The script does occasionally slip into unnatural monologuing, but on the whole it's believable and illuminating – exposing the tensions that flow from these different backgrounds, without ever lecturing us on them. Among the cast, Russell Shaw stands out as the Boer War veteran, ably maintaining a complex balance between military pragmatism, subtle insubordination and remembered hurt. A new dimension is added later, with the arrival of a German captain – played by Neil James with perfectly-pitched cynicism (and a spot-on accent, too). He's seen enough of war to be willing to bend the rules, and he delivers a chilling reminder that – though the tank crew cannot win this battle – they do have a choice about how many Germans they kill.

This whole story is told in a single continuous scene, compressing three or four days' action down into an hour. The absence of breaks or transitions is a bold choice, but I don't think it quite pays off. Sometimes it's unintentionally comic – a character comments that night is falling, and it goes dark as though a switch has been thrown – and a couple of times it's actively confusing. It was only towards the end of the play that I realised the tank was meant to be stranded several miles from friendly lines; we'd witnessed its journey squashed down to a few seconds, so my natural intuition told me it had only travelled a short way.

The tank-interior set is impressive in its ambition, and sound and light effects successfully convey both the suddenness of assaults on the tank and the quietness when they subside. There's a limit to how much you can do in a Fringe venue, though, and paradoxically I think a more stylised approach might have been more effective. At times the clattering and banging outside the tank drowned out key lines – and at one point a character died literally without me noticing, because I'd been distracted by eye-catching action on the other side of the stage.

For a long time, I thought the script had painted itself into a corner: that there was simply no satisfying way this stand-off could ever end. But no, I was wrong; there's a clever, stark and visually striking conclusion, which ties up some of the plot-threads and leaves others for us to imagine. Overall then, while Bully Beef has its weaknesses, it's an impressive statement of intent from a relatively new playwright – a thoughtful approach to a still-relevant topic, done justice by a committed and credible cast.