When a cop claims to be seeing his wife behind his back, Captain Stottlemeyer loses his temper and punches him in the face. Because of this, he is forced to take an anger management course as a way to learn how to control his temper. When confronted about the situation, his wife is offended that her husband would ever believe such an obvious lie. Even though she denies all the accusations, Captain Stottlemeyer recruits Monk and Natalie to follow his wife around town and see what she's up to. What neither of them realize, is that this entire situation is tied to the mysterious murder case that they're working on.