Review: Baby Reindeer (Summerhall Roundabout, Edinburgh)

Scottish writer and actor Richard Gadd has an unnerving knack for taking personal experiences and transforming them into utterly compelling, disconcerting pieces of work. His award-winning 2016 Fringe stand-up set Monkey See, Monkey Do could quite easily have sat neatly in a theatre section of a Fringe brochure.

So it's no surprise that he now makes an official leap into 'theatre' with 70-minute solo show Baby Reindeer. It's based on an episode he had when, working in a bar from 2012, he encountered 42 year-old Martha. Claiming to be a high-flying lawyer with a plush pad in Pimlico yet stating she's unable to afford a cup of tea, Gadd is initially intrigued by her presence – only later does he realise he's caught the attention of a serial stalker.

The performer doesn't do anything as blunt as a cookie-cutter demonisation of Martha, explicitly acknowledging the fact that she is likely mentally ill, and certainly in need of help. Instead, he whips the focus back and forth between his stalker and his own, fractured masculine ego that has compelled him to indulge her obsession. "She's the one person that sees you as you want to be seen," Gadd's partner Teri states. You baulk as you watch him recite all the times he goaded Martha on, reluctantly toying with her affection.

Because this is a piece about the destructiveness of pride, Gadd's self resentment bubbles through, he claws at his red long-sleeve shirt as if feeling unclean. The man questions his identity, his career as a comedian, the psychological impact of having a trans-woman as a girlfriend. A patchwork performance of a man coming apart at the seams.

It's an uncompromising, uncomfortable watch that leaves a bitter taste swilling around the back of the throat. But there's something to be said for theatre that is harsh and sometimes relentlessly cruel. It can make the stomach churn – we simultaneously resent our protagonist and sympathise with his plight.

Anyone with any knowledge of Gadd's work will know to go in expecting a brutal intensity – words and transcripts are projected onto walls with disorientating speed, wiped away before we've had a chance to fully read them (courtesy of Ben Bull and Stoph Demetriou). Lights burn, Gadd rants and raves as Martha, now equipped with an email address and a phone number, continues to send thousands of messages. Before long it's phone calls, sound designer Keegan Curran washing answerphone recording over after answerphone recording. Jon Brittain's production is a bombardment of the senses and emotions.

Gadd places the imaginary Martha on a bar stool atop a grey, revolving plinth at the centre of the stage. She's surrounded by the audience – we're complicit in her interrogation as if she's standing on trial. Cruelly cool and pitched perfectly, Gadd has transitioned from comedy to theatre with a disgraceful grace.

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