After Leo is killed during an undercover operation Rollie and Angie are helping on, Rollie tries to find out who did it and try to get around an Internal Affairs officer impeding his efforts.
Angie, and then Rollie reluctantly, get involved in making a documentary with a director focusing on a mob boss, but the director has more in mind than merely filming said boss.
An accountant on the run from the mob offers the man who ordered Leo McCarthy's murder in exchange for faking his death. When Gatti learns of it, he goes undercover without permission, imperiling his life.
Victor Loubar is back from the dead and seeking a deadly biological agent to kill untold numbers of people. With the help of Rollie and Angie, agent Elena Serrano returns to try and stop Loubar.
After Sanchez says she has promised the widow of a Scotland Yard detective who is murdered after being thrown from a plane she would solve the murder, Rollie helps Angie, Sanchez and an actress go under cover on the flying casino to close the case.
Rollie and Angie fool an delusional imprisoned man who murdered a politician in 1979, into thinking it's still 1979 so they can uncover what really happened then and who was involved.
Ricky Delacruz, a mass murder, avoids prison time and goes after Rollie for almost putting him there. Rollie and Mira set about trying to put him away for good, but a crooked lawyer causes problems.
An arsonist is burning down buildings using jet fuel and making it look like accidents, leaving Rollie to figure it out once a film set burns down and he is implicated.
After the daughter of the director Rollie and Angie are working for is kidnapped and held for ransom, the two must try and work on the fears of the only man who can lead them to her before she's dead.
Rollie goes undercover as a high-priced jewel thief to help the police department capture an elusive and technologically sophisticated jewel thief simply known as Sebastian.