Kat Ryan is looking forward to a peaceful week attending a conference in Boston, Massachusetts, away from California, the stress of her demanding job, and the latest upheaval in her personal life. Clara Dunfey was not looking forward to another boring day of retirement from the Boston PD. A mistaken identity starts a violent chain of events that leads the duo from Boston to California as they try to solve the mystery behind a kidnapping that eventually leads them to a murder.