GUNPOWDER, a three-part thriller based on the real-life 17th century events that led to Guy Fawkes Day, will debut on HBO this December. GUNPOWDER stars Kit Harington as Robert Catesby, who was the driving force behind the Gunpowder Plot in 1605 London. A committed Catholic at a time when Protestant England persecutes Catholics relentlessly, Catesby’s refusal to abandon his religion brings him to the edge of financial, social and psychological ruin.