Review: 31 Hours (Bunker Theatre)

Kieran Knowles' play takes its title from the statistic that every 31 hours somebody commits suicide by hurling themselves in front of a train. Apparently men are ten times more likely than women to attempt this, and Knowles' piece is a terse, testosterone-fuelled quartet that centres on a group of men who clean up the railways after the deaths. It makes for undeniably grim viewing at times, but is also admirably unsentimental and contains a sometimes surprising leavening of gallows humour.

All four actors are clad in high visibility jackets and helmets and they collectively portray a wide spectrum of characters – including a patronising maintenance manager, a therapist, a hilariously clueless social media manager, a pair of pensioners tragically driven to end it all when their savings run out – as well as the blokey central quartet. The overall effect is similar to the stage version of Trainspotting (no pun intended) with its sometimes bewildering array of voices and situations.

Abigail Graham's abstract, high energy production might benefit from concentrating more on defining and delineating the individual characters, and less on the rather wearisome moving around of the metal planks on Andrew D Edward's stark set – sometimes giving a sense of new locations, other times for reasons not entirely clear. This proves impressive mainly as a feat of memory for the actors but doesn't make for especially stimulating stage business. There were times when I found myself alienated from the heartrending human stories by the overly complex staging.

As a script, 31 Hours is, to be fair, more of a kaleidoscope of despair than a traditional play, so it would be well nigh impossible to emotionally connect with every situation depicted. One of Knowles' undeniable strengths is an unerringly accurate ear for the way real people talk and the play forces us to consider – possibly for the first time, for many people – what the effect of clearing up the post-suicidal mess must be on the professionals who do it.

The cast – Salvatore D'Aquilla, Abdul Salis, Jack Sunderland and James Wallwork – is superb, switching roles in the blink of an eye, impressively transitioning from laddish swagger to raw pain then back again. They credibly convey a sense of grim team spirit among the men doing this essential but harrowing work. Wallwork and Sunderland are especially adept at differentiating between the various characters they portray, but all four of these fine actors gets their moment to shine, most notably D'Aquilla whose solo speech – a howling, despairing riff on the throwaway term "man up" – is genuinely unsettling.

Despite my reservations, this is meaty, vital theatre: as a plea for empathy and communication, it is frustratingly hard to connect with at times, yet it still sends you out into the night with a lot to mull over.

31 Hours runs at the Bunker Theatre until 28 October.