When ex-cop Stu Peterman is acquitted of murdering his wives, he does what anyone in his situation would do: he starts giving seminars on "How Murderers Get Caught." As spouses start dropping like flies, Detectives Division and Rush must stare down an angry mayor, a mutinous football team, a reality TV star, an improbable army of Stu Peterman groupies and an investigative reporter with a little too much drive as they try to make the city safe for bickering couples.