Rather like the high-octane escapades of the title character in Penny Gunter’s new play Dorian’s Second Life, one-man shows are inherently risky. Sharing the stage with nothing other than an imposing mass of scaffolding and a length of nylon webbing is asking a lot of Dean Rehman. Thrillingly, he delivers in spades, with a taut, sinuous performance as an adrenaline junkie pathologically addicted to fear. Dressed in a loose-t-shirt, shorts and a rustic necklace, he is a desert island outcast of the city, baring his soul to the audience before another walk on the high wire.

Sita Calvert-Ennals paces the piece well, with performance, lighting and sound design colluding to bring out all the nuances of Gunter’s subtle and engaging text. Crucially, the various strands of Dorian’s story past and present are given time to breathe and develop before being brought together, and though there may be a slight loss of momentum towards the middle, the understatedly moving conclusion that the stage is being set for is worth it. In fact, the level of depth achieved in less than an hour is truly admirable: you are unlikely to find as much unfussy intensity per minute anywhere else in Bristol.

It’s true that Rehman has a notably well-researched and plotted script to work with, but it is his focused maintenance of a physical and mental edginess from beginning to end which makes Dorian’s Second Life such an intriguing character study. At our first encounter, Dorian is a stranger reciting a list of bodily injuries and tightening bolts, oblivious to the entering audience. By the evening’s end, we have been amused and shocked by him, and are well acquainted with his needs, his regrets and perhaps most chillingly his foibles. He informs us at one stage that he “hasn’t come here to listen” and he is right – that is the role played by theatregoers, held in the thrall of Gunter’s gripping creation, brilliantly realised on stage.

Dorian’s Second Life is playing at the Alma Tavern and Theatre until 29 October. For more information and tickets, see the Alma Tavern and Theatre website.