The Strangler spent two years murdering women in Chicago. It's been eighteen months since the last murder, and the police are desperate to make an arrest. When the FBI gets involved, Olivia and Nate find themselves teaming up with an old friend. The three of them have their work cut out for them trying to profile a murderer who is indiscriminate in his victim selection. Will they find the Strangler before he can find his next victim?