Detective Ren?e Ballard is working the night beat -- known in LAPD slang as ''the late show'' -- and returns to Hollywood Station in the early hours to find a stranger rifling through old file cabinets. The intruder is retired detective Harry Bosch, working a cold case that has gotten under his skin. Ballard can't let him go through department records, but when he leaves, she looks into the case herself and feels a deep tug of empathy and anger. She has never been the kind of cop who leaves the job behind at the end of her shift -- and she wants in.