Mark Thomas is worried he's going legit. Having spent years pricking the establishment's side, he was praised last month by a commons select committee for helping expose the illegal UK arms trade. That campaign is the subject both of his new book, As Used on the Famous Nelson Mandela, and this stand-up set. The show recounts Thomas's undercover adventures among arms dealers, and his existential crisis: is he a comedian, an investigative journalist or a collaborator with the powers-that-he-wishes-weren't?
Well, he's certainly a comedian, even if his hurry to communicate the show's surfeit of information sometimes comes at the expense of comic timing. There are killer lines here, including this one spoofing the government's feigned surprise when Indonesia uses British-sold tanks on its civilians: "Turns out Indonesia are not the off-road enthusiasts we thought they were." And there's an entertaining riff on why fatal car crashes, like arms deals, might be considered "good for the economy".
But it's not Thomas's on-stage shtick that engenders astonished laughter, so much as his real-life adventures. His activities are his art - tonight, he merely makes report of them. Here are stories of sharing egg-and-cress sandwiches with sponsors of torture, and of a Kalashnikov salesman complaining that shop assistants are insufficiently polite. Here is Thomas's friend being questioned in Parliament Square, under new anti-demo laws, for eating a cake with the word "peace" picked out in icing - for the sake of our security, apparently.
Like Michael Moore, Thomas cultivates an everyman blokeishness, characterising others as "posh" and claiming to feel nervous at the hands of police and Tory MPs. And, as with Moore, I'm happy to accept that ego is a professional necessity and populism a price worth paying to persuade us that anyone could (and should) be as vigilant against injustice. Like all of Thomas's work, this exposé of the arms trade is also a call to arms.
· Until Saturday. Box office: 0870 429 6883. Then touring.
