I first came across Mark's work through legendary British comic 2000AD. He's illustrated everything from Durham Red to Pulp Sci-Fi but I particularly remember his visceral art for Gordon Rennie's Glimmer Rats.
However, roughly eight years after Glimmer Rats I found myself working with Mark myself. He realised the cover for Unnatural History - featuring a duel atop a steam train and a T-Rex with St Paul's Cathedral in the background - and since then has produced every Pax Britannia novel cover (including Al Ewing's El Sombra and the forthcoming Gods of Manhattan).
You can visit Mark's own website here, and see his other novel covers, alongside his comic artwork and concept paintings for computer games.
Meanwhile, here are his six Ulysses Quicksilver Pax Britannia novels to date in their full gruesome glory.