In the Rizzoli & Isles Season 5, Episode 16 episode " In Plain View ," the team investigates the murder of Todd Reynolds, who was found dead on the side of the road. The case centers on a visiting detective, Mike Guthrie, who is revealed to be the killer acting on a long-held grudge from summer camp. Alongside the main investigation, Maura Isles tackles her own identity theft with the help of Angela Rizzoli, resulting in the imposter's arrest.
You can find the episode on Apple TV and read more details on the Rizzoli and Isles Wiki . "Rizzoli & Isles" In Plain View (TV Episode 2015) - IMDb [S5E16] In Plain View