Dr. Alexander J. Mercer is the former head researcher of the Blacklight project at Gentek. After learning that his fellow researchers were being murdered, Mercer attempted to flee the city with his research contained in a vial. Mercer experienced a brutal childhood spent in abject poverty; his first nine years were spent in foster care. He was the only parental figure for his sister, Dana. As kids, he and Dana would play together and watch scary movies. He knows MMA. Has brown hair, blue eyes.