As an actor, Marcus has performed lead roles and ensemble parts in productions across the London fringe and the UK, including:
The Great Cat Massacre (Chats Palace), An Evening with Mr. Theatre (Rosemary Branch), The Dog Beneath The Skin (BAC), A Christmas Carol (St. David’s Hall, Cardiff), Cut Out and Keep…(BAC, Lion and Unicorn), The Spaceman (UK Tour), The Lusiads (Wireframe at The Bargehouse), In Stitches (BAC), Piper - The Forgotten Story (Secombe Theatre), On the Barges (Players Theatre), Sodom (Edinburgh Fringe), Pleasure Palaces (Lyric Hammersmith), A Cautionary Tale (NT Studio).