When Sister Mary Aurelius is murdered in front of the shuttered Immaculate Conception school outside of Boston, former student Rosaria O'Reilly is determined to find justice for her mentor. The Malford Police have identified a mentally unstable homeless man as the killer, but Rosaria wasn't trained to settle for the easy answer. With help from a close childhood friend, Nuncie DiStephano, now losing the struggle with an aggressive cancer, her investigations unravel a much larger, more sinister story. Working sometimes as an adversary, sometimes as a partner with Malford Police Detective Leo Gelenian, she pieces together the motive, method, and identity of the murderer through confrontations with a powerful real-estate developer, a vicious Boston crime boss, and an autocratic monsignor with passionate ambitions for his prestigious Catholic high school. The Immaculate is a complex murder mystery with a deep sense of place, a compelling storyline, richly developed characters, and a satisfying surprise ending.