The 14th precinct has an informer in its midst. The undercover agents working on a truck hijacking are getting exposed. IAD ""asks"" C&L to investigate, since they're ""outsiders."" When Cagney refuses, the IAD lieutenant smirkily tells her that Charlie was on the take when he was a cop. All they turn up is that LaGuardia has a girlfriend and Samuels is seeing aa psychiatrist because of the effect of his divorce.

Cagney's car (a yellow Corvette) has been stolen and boy is she mad. She doesn't get much help from Mary Beth, who is convalescing at home and considering quitting for good. The good news is that the second half of the sergeants exam has a question about auto theft technique.The episode introduces Hector (El Vengeador). It is later learned that Cagney's nemesis Mansfield had him murdered for his role as a drug informant in the episode ""The Man Who Shot Trotsky