Washington City - October, 1861. Civil war is upon us. A spy among us. A mysterious code hides a deadly secret that could change the tides of war. The key to the code, and the fate of the nation, rests in the hands of a young police officer named Levi Love. Answering President Lincoln's call, 75,000 volunteers descend upon Washington City and transform the nation's capital into a den of violence and vice. When a beautiful young woman is found dead in one of the open sewers that plague the City, Levi is ordered to investigate. The evidence leads to a mysterious code that confirms a terrifying fact - a murderous spy is hunting the nation's deepest secret. The clues soon draw Levi deep into the City's underground slave trade. There, he meets a freedman named Josiah Johnson who has information that can help crack the code and identify the Confederate spy terrorizing the City. As the murders continue, Levi and Josiah track the spy from the darkest corners of the City's brothels and alleyways to the grand ballrooms of the ruling class. Together, they must unmask the spy before the secret gets out and the high-stakes game of war is lost.