A member of The Royal Shakespeare Company on stage, Quarshie has performed in TV versions of A Midsummer Night's Dream (Philostrate), Titus Andronicus (Aaron the Moor), and the animated Julius Caesar (Cassius). However, Quarshie has been more active before the cameras in a variety of high profile science fiction and fantasy projects, including Highlander (as Sunda Kastagir), Star Wars Episode 1: The Phantom Menace (as Captain Panaka), Nightbreed, and TV appearances on The Tomorrow People, BeastMaster, Red Dwarf, and Doctor Who (as Solomon in two 2007 episodes). Other TV credits include the hospital drama Holby City (a regular since 2001 as Ric Griffin) and episodes of Rumpole of the Bailey, The Bill, and Press Gang.