As the team investigates the murder of a young woman found inside a piece of luggage at the airport, Carlo contends with buried secrets from his past.

The hunt for a killer who stabbed a nun inside a sex shop takes a perilous turn. Back at the station, the team meets Santagata's successor.

One mystery leads to another when DNA from the body of a recently murdered woman is traced to a man who's been dead for months. Guilt weighs on Alba.