The sky is burned to orange and society has fragmented. Anyone that is not fully human is ostracized or worse. Aria Brayton, age twenty-three, is an Opus, a high skilled and genetically enhanced assassin with an AI. She has been on the run from the government and Project Maestro, the place that made her what she is, for the past three years. A wanted poster for her arrest and a group of people with AIs chasing after her spark her journey back to Project Maestro. She must put aside her past in order to help out the man in charge of the program, Major John Stratton. Tragedy, a desire to protect her sister, and an escalating issue with the group called Fugue cause Aria to face them alone, at great cost to her and her AI Piano.