Half man, half beast, Vincent is the recipient of unconditional love in his underground home-a Utopian society of outcasts living in a network of tunnels that were once part of an old subway system-yet he had never truly known the love of a woman. Walking through Central Park one night, he stumbled across a woman who had been brutally attacked and left for dead. Breaking an underground rule and risking the exposure of the home of those who depended on him most, Vincent carried the woman there, and with the help of Father-the leader of the society below-nursed her back to health. He learned her name was Catherine. With her face being covered in bandages because of being slashed, she couldn't see the face of her caretaker. After the initial shock of Vincent's appearance, the two formed a bond stronger than love, and Vincent became not only her protector, but the love of her life. Then, three years later, Catherine was kidnapped and killed after giving birth to Vincent's child, a beautiful and perfect son. Vincent was crushed by her loss and vowed to find her killer. Diana Bennett, a detective for the police department, took the case, and together, they found the killer and Vincent was reunited with his infant son. A friendship formed between Vincent and Diana, and the people below welcomed her, entrusting her with the knowledge of their secret world, knowing she would never expose them. Never allowing herself to be emotionally involved in a case, Diana's head told her what she felt for Vincent was nothing more than compassion for his loss. But her heart felt something entirely different. Catherine's death brought to Vincent a pain so great, he vowed to treasure his love for her forever, never allowing another in. But that was before Diana. This is their story.