Mark is one of the newly discovered Castor clones and was a loyal follower of the late Prolethean leader Henrick Johanssen. When the Prolethean Ranch was burned down by Helena, Mark vanished with Johanssen’s waifish daughter Gracie, who he’d fallen deeply in love with. But as one of many male clones created by the military, the question remains, who is Mark? Why was he with the Proletheans? And in the face of this newfound love, where do his allegiances lie?