1. Bridget Moynahan as Erin Reagan-Boyle
In Blue Bloods' "With Friends Like These" (Season 6, Episode 4), Erin attempts to convict a slippery mob boss for an old murder. Unfortunately, the case is muddled when her former informant, Vincent (Dan Hedaya), leaves witness protection to provide his old boss with an alibi. Also, Frank finds himself in a departmental war with Commissioner of the New York City Fire Department, Stan Rourke (Dan Lauria).