A bottle of wine, a comforting hug, a shy kiss which led to more: Rob might have made a mistake. He’s not sure. He and his best friend had sex last night. They’ve known each other for years, went to school together and played together. But she left for work early this morning and Rob hasn’t been able to concentrate all day. Eager to talk to her about the previous evening, he’s bought a bottle of wine – another one – and is waiting on Stacy’s doorstep for her to come home.  But it’s Stacy’s flatmate Shona who arrives first and as they wait, things start to fall apart.

One man, a chair and a projector are all that PlayON Theatre’s production of Stacy uses to embellish Jack Thorne’s play, currently showing at the Pleasance Islington. All focus is on Rob, played by the slightly nervous but engaging Nic McQuillan. Rob is a conundrum of a character and the more he reveals of his life, the more opaque it becomes. Was he actually the favourite child, apple of his parents’ eye, the one people stopped on the street to say how beautiful he was? How did he end up in his dead-end, dead-boring call centre job? What is the significance of the dead dog in the street? What does ‘best friend’ Stacy really think of him? And for every part of the tale, do we believe him – or are we just being dragged into an unreliable narrator’s version of reality, into the confessions of an unjustified sinner?

Jack Thorne’s credits include TV (working on Channel 4’s Skins and Shameless, and alongside Shame Meadows on This is England ’86 and ’88) and radio (he won a Gold Sony Radio Academy Award in 2010 for his Radio 3 play People Snogging in Public Places) as well as theatre. With such a pedigree – and as a fan of This Is England – I was pleased to see Thorne’s history of hard-hitting writing continued in Stacy, which does not shy away from the awkward or make compromises to shield an audience from discomfort (here’s the disclaimer: if you’re squeamish about hearing tales of bodily fluids, and/or shy about images of granny sex and male genitalia then prepare for fingers-in-ears and eyes-on-floor moments) but it is in this uncompromising honesty that the piece finds much of its humour. We are drawn in, side by side with Rob as he expresses his confusion about Stacy and his uncertainty about women and relationships. The complicity built up between audience and performer, dealing with transgression in matters sexual, is reminiscent of Tim Crouch’s 2009 play The Author in which there was the same, slightly shifty ‘Does he know he’s saying that out loud?’ feeling created by Thorne.

Only an hour in total, Stacy would benefit from a slightly quicker and more even pace to keep up the narrative edge and, as McQuillan dives offstage almost without warning, the ending lacked quite the punch I expected, leaving an abrupt up-in-the-air feeling to the piece as a whole. Despite that, though, Stacy is a well-worth-it monologue of a boy lost, a love story gone awry, a 60-minute tale of neurosis and almost-adulthood, and a confession from a young man who has no idea how he ended up here.

Stacey is playing at the Pleasance Theatre until 29 January. For more information and tickets, see the Pleasance Theatre website.