Mark plays conceptual artist Brian Topp in this dark Channel 4 sitcom written by Simon Pegg and Jessica Stevenson (Hynes) and noted for its rapid-fire reference to pop culture and surrealist non-sequitors.

Brian is the lodger in the flat below Tim and Daisy's, Brian is a rather bizarre and somewhat angst-ridden and pretentious artist. Quietly spoken and intense, Brian gives the impression of being almost psychotic and sociopathic; in fact, he's just very shy and timid.