Thermodrama - Edinburgh Fringe Festival 2026

​Four people enter a sauna. Three walk out. in Coco Cottam’s Thermodrama, a group of strangers get progressively hotter as their worlds begin to close in around them, offering a darkly comic look at the costs of a culture obsessed with self-improvement. While Summerhall’s sauna venue has attracted plenty of attention this Fringe, Thermodrama is based in the venue but producing its own sauna effort transforming a theatre space into something equally steamy and warm. 

At the centre are estranged half-sisters Sophie and Jenny, alongside Pete, a gym devotee whose life revolves around optimising his body, sleep and readiness score. Matty Loane plays Peter as a pitch perfect tech-bro life-hacking preacher with a temple for a body. Yet the real subject of Thermodrama is not simply self-improvement, but what happens when we become so consumed by ourselves that we stop noticing the people around us.

Pete is so absorbed in his own routines that he cannot recognise Sophie’s attempts to connect with him. When she tries to turn their interaction into something intimate, he retreats into visualisation exercises and self-optimisation. Sophie, meanwhile, becomes so fixated on Pete that she fails to notice Jenny trying to share exciting news about a new romance that could take her from the UK to Turkey. Even the most extreme example is Pete’s failure to notice a man covered in blood entering the sauna. Everyone is physically crammed together, yet emotionally they exist in entirely separate worlds.

That idea gives the play some of its strongest moments. The sauna becomes a pressure cooker for modern self-obsession, where everyone is sweating, talking and performing versions of themselves while remaining remarkably incapable of actually seeing one another.

The trouble is that Thermodrama builds very slowly towards a dramatic turn that never quite earns its impact. Midway through, a bloodied stranger enters and the promised consequences begin to unfold, but the shift into chaos feels more like whiplash than culmination. The development introduced in the opening description, that one person will not leave the sauna, ultimately feels disconnected from the more interesting ideas the play has been exploring. 

That is particularly frustrating because the immersive quality of Thermodrama is one of its greatest strengths. The transformation of the theatre into a sauna creates a genuinely oppressive atmosphere, making the audience feel the heat alongside the characters. The sudden dramatic escalation pulls us out of that carefully constructed world.

Lee Hutchison

3.5/5

Runs at Summerhall until August 31st