Roger Ma specializes in hand-to-hand combat against the undead. He is the author of The Zombie Combat Manual: A Guide to Fighting the Living Dead and The Vampire Combat Manual: A Guide to Fighting the Bloodthirsty Undead. His work focuses on battling the undead using only hand-to-hand weapons and unarmed combat. He was featured as a zombie expert on the History Channel documentary "Zombies: A Living History." He is a purple belt in Brazilian Jiu-Jitsu and lives in New Jersey.