An undercover FBI agent is killed on a Marine Training ground. They soon discover more bodies in the area. Gibbs offers a joint investigation with the FBI, but Fornell refuses. In private, Fornell tells Gibbs there's a mole in the FBI, and asks for his help in finding him. The FBI suspects Fornell is the mole. NCIS must track down the real mole to save Fornell.
This series is based on the author's teen years in Montreal after World War 2, in the northern district of Villeray, and during the summertime in Pointe Calumet, a quiet vacation spot northwest of Montreal.