You've maybe seen the YouTube video, where a former English teacher makes mincemeat of a teenage grime artist in a rap battle. That man was Mark Grist, who, following his 15 seconds or so of internet fame, began a second career as a 'rogue teacher', swapping the classroom for the battlefield of rap.
His one-man show takes his audience on a journey from the classroom to the battleground of the spoken word.
The story begins when he enters the teaching profession, something he'd first dreamed of as a child. But when reality failed to live up to his hopes, and he left in the middle of the recession to embark on other challenges, he decided to try his hand at 'rap battle' (underground contests in which rappers direct vicious insults at each other).
"It's quite a distinct art form, separate from page poetry," he said.
"With page poets, they seem distant, like they're hiding away. Rap battling is high-stress; you get a great nervous energy.
"I enjoy the restricting elements rap battling enforces on you, creativity comes from being restricted."
His contest against 17-year-old Blizzard is the one you'll have seen online – and the one that propelled him to stardom.
You'll hear Mark's rendition of a univocalism (a poem which uses only one vowel), and a brutal rap battle he's written against his teenage self.
Mark's happy to rap for the foreseeable future, but he's got other plans as well: "I'll do rap battling for another year, but I'd like to produce another piece of work to be remembered by. I won't always be 'that guy from the YouTube video'."
His next target may surprise some: "I do miss teaching, I might go back in a few years. It's really amazing that I've got to do these things, it's nice to mix it up a bit."
You can hear him mixing it up when he plays OTL at the Black Box today at 1pm.