I've seen some bad comedy acts over the years – but not, until now, one that is part of an existential threat to humanity. One of artificial intelligence's pre-eminent boffins, Geoffrey Hinton, sent out shock waves recently by arguing that, in relation to AI: "We're toast. This is the actual end of history." That's a hell of a backdrop to my visit to see Artificial Intelligence Improvisation, a show by the Improbotics troupe playing as part of an AI festival in London this week. You'll forgive me, I hope, for some hesitation in wielding the critical brickbat, given that the act under review boasts the capacity to wipe out all of us.