There is something inherently unsettling about agreeing to take a lie detector test, particularly when the results are going to be shared with a room full of strangers. Australian company Counterpilot has built Truthmachine around precisely that proposition, using real biometric sensors and live voting technology in a thirty-minute immersive experiment.
This was a new C Venues space for me, above Victoria Street. Two flights up, we were ushered into a darkened room dominated by a long table, six seats on either side, each equipped with headphones, microphone and voting panel. At one end sat our questioner; at the other, an ominous chair surrounded by the equipment into which one of us would eventually be plugged.
It is an impressive set-up: clinical, mysterious and technologically sophisticated. Seven of us occupied the twelve available seats, four people who knew each other, two young women together and me. We spread ourselves around the table, put on our headphones and entered the experiment.
Initial yes-or-no questions establish our willingness to participate. Would I submit to the lie detector? Absolutely. Sadly, I wasn’t selected. Instead, one of the group of four took the hot seat, immediately adding another psychological dimension because several people around the table actually knew him.
An interrogator entered and our subject was connected to the polygraph, monitoring physiological responses including heart rate and galvanic skin response. Counterpilot cleverly translates those tiny changes in the body into sound and light, making the data itself part of the theatrical environment.
The questioning began relatively playfully. Did he find his interrogator attractive? No. Would he make love to her? Again, no. His interests, I suspected, lay elsewhere. From there things became considerably more probing, but revealing those questions would rather defeat the purpose of experiencing Truthmachine.
I remained fascinated by the technology and increasingly interested in the psychology developing around the table. Yet I also found myself waiting for all this impressive apparatus to lead somewhere.
For me, it never quite did.
There is undoubtedly an intriguing theatrical proposition here, but the technology ultimately proved more compelling than the theatre surrounding it. The experiment seemed to fizzle out rather than reach a satisfying conclusion. Most frustratingly, towards the end there appeared to be a whispered exchange between interrogator and subject to which the rest of us were not party.
I left wondering whether I was supposed to seek out our human guinea pig afterwards and ask what had happened. But surely, I shouldn’t have to. Whatever revelation or uncertainty the production wants to leave us with needs to exist within those thirty minutes.
Truthmachine is slick, unusual and technically accomplished, and its clinical atmosphere is extremely well realised. Counterpilot has created something genuinely distinctive, and the underlying questions about truth, technology and our willingness to believe what machines tell us are fascinating.
But there is something here that hasn’t quite found its final theatrical form. I entered wondering whether a machine could successfully detect a lie. I left wondering whether Truthmachine had quite proved its own case.
Playing until August 30th 2026, https://www.edfringe.com/tickets/whats-on/2026TRUTHMA
Reviewer: Greg Holstead
Reviewed: 26th August 2026
North West End UK / Theatre Muse UK Rating:
Running time – 30mins