Before dawn, a blue house on Harbor Street goes up in flames. Inside, retired marine electrician Arthur Bell is found dead. Outside, detectives find Erin Kessler—barefoot, bloodstained, and carrying the key to his home. Erin insists she has nowhere to live and no reason to hurt him. But every answer she gives changes the story: she never knew Arthur, then he was her employer, then she only stayed in his house sometimes. As Detective Mara Vale follows a trail of burned fabric, a hidden notebook, and footage the fire failed to destroy, she discovers that the truth behind the blue house is more heartbreaking than anyone expected.