Leonidas is chained up in our research hospital for everyone's safety, since he's been infected by a demon.
This man has no last name, no past, but plenty of secrets. He insists he's a Knight of the Light, with powers to fight the forces of darkness, and we are holding him captive. But I can't let him go, he needs help. The sickness is changing him, turning him into something dark and dangerous.
Then when the demon who infected Leonidas escapes and starts razing a bloody path through the hospital, I have only this knight to rely on if we want to get out alive.