Undersigned review – put on a blindfold and reveal your desires in intimate one-to-one

Yannick Trapman-O’Brien’s disarming show is akin to having someone drawing your portrait as he steers a probing conversation

I have been banned from this show. As will you be, if you can nab a ticket. Part of the thrill of this intoxicating slice of occultism, designed for one blindfolded audience member at a time, is your lack of knowledge going into it. No one is allowed to go twice.

What takes place is a summoning, a ritual both dark and deeply sentimental. Through gentle, probing conversation, creator Yannick Trapman-O’Brien demands to know what you desire, and what you are willing to sacrifice to get it. As he leaps and twirls around your mind, his dexterous chatter is confronting, charming and sharp as a pinprick.

The simple structure, framed around ideas of traditional witchcraft, guides you in a way that responds specifically to your comfort levels and the depths you are willing to dive to. Requested topics can be off limits, but ideally you’ll be OK with blood. The show’s inebriating effect is akin to the intense focus of someone drawing your portrait, or reading your tarot, or giving you therapy. It is a magic trick of sorts, lulling you into openness. With the blindfold disarming my senses and a crackling candle by my ear, a vertigo effect makes the voice I hear simultaneously distant and close enough to touch. My hands start to feel heavy and I hear myself saying things I didn’t plan to share.

The final 10 minutes offer a gift of a different kind, with a glimpse into the thinking of the participants who have gone before. Seeing how others responded to the same prompts is revealing about both parties; there are so many conversations here that I would have liked to press my ear to the wall to catch.

With delicious playfulness and an underlying earnestness, Undersigned encourages indulgence and challenges your moral makeup. Through its supernatural proclivities and Trapman-O’Brien’s balletic conversation, the show sends you back out into the world looking at it a little more rosily. By asking what you want, Undersigned makes you appreciate what you already have.

• At Underbelly, Cowgate, Edinburgh, until 12 August
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