In House Blood, Joe DeMarco, a legal investigator on the staff of former Speaker of the House John Mahoney, is asked to look into the murder conviction of a former lobbyist. His heart isn’t really in it, but when he starts reviewing the case, he discovers a pharmaceutical company has been testing a new unknown drug on humans in different parts of the world and the company has been using natural disasters to hide what they are doing. As the investigation continues, DeMarco becomes the target of two assassins and must figure out how to stop them before he becomes their latest victim.