Lindsay, Claire and Jill cautiously welcome a new member to the Women's Murder Club, young reporter Cindy. Meanwhile, Lindsay and Jacobi investigate a homicide committed by a serial murderer dubbed "The Vendetta Killer". In their private lives, Lindsay faces up to the past when her ex-husband is brought into her police department in a leadership role, Jill faces a domestic crisis, and Claire struggles to help her husband, who's fighting depression.