Movies Like The Departed

Frequently asked about The Departed

Common questions people search for, with answers written by us at MoviesPack.

• Why does Colin Sullivan (Matt Damon) kill Captain Queenan?▾

  Sullivan does not directly kill Queenan — Costello's men throw Queenan off a rooftop after capturing him during a sting operation that Sullivan had tipped off. Sullivan's culpability lies in leaking the location of the meeting to Costello, which led directly to the ambush. The killing serves to demonstrate how Sullivan's loyalty to Costello overrides any loyalty to the police department, even when it means the death of his own superior.

• What is the significance of the rat that appears at the very end of the film?▾

  In the final shot, a rat is seen walking across the balcony railing overlooking the Massachusetts State House — the same view from Sullivan's apartment. Scorsese uses the rat as overt visual symbolism: throughout the film both Sullivan and Costello refer to informants as 'rats,' and the image underscores that Sullivan, despite executing Dignam's colleagues and nearly escaping justice, is himself the ultimate rat who has been embedded inside the system the entire time. It is a deliberate, unsubtle punctuation mark on the film's central theme of institutional corruption.

• How does Billy Costigan (Leonardo DiCaprio) know that there is a mole in the Special Investigation Unit?▾

  Costigan pieces it together gradually: Costello's crew consistently evades or anticipates police operations in ways that can only be explained by inside knowledge. The clearest confirmation comes when Costello himself tells Costigan that he has 'a cop on the payroll,' and Costigan later finds that sealed SIU files have been accessed. He attempts to relay this to Queenan, but the only way to identify the mole with certainty requires getting Costello's phone records — which is the thread that ultimately ties Sullivan to Costello's number.

• Why does Frank Costello appear to be working as an FBI informant, and how does it affect the plot?▾

  Late in the film it is revealed that Costello had been an FBI informant for years, effectively using that relationship as a shield against federal prosecution while continuing to run his criminal empire. When Sullivan discovers this, he realizes that Costello is a liability who could expose him; this is the primary reason Sullivan shoots Costello himself rather than allowing an arrest, framing the killing as a necessary police action. The revelation recontextualizes Costello as a man who played every institution — police, FBI, and his own crew — against each other for his own survival.

• What leads to Costigan's death in the elevator, and who kills him?▾

  Costigan has just arrested Sullivan and is transporting him when the elevator opens to reveal Trooper Barrigan, a corrupt cop who was also secretly working for Costello. Barrigan shoots Costigan in the head without warning, then kills the other officer present. Sullivan is visibly shocked — he was unaware Barrigan was another mole, meaning even Costello kept his informants compartmentalized from each other. Sullivan then shoots Barrigan, eliminating the one witness who could have corroborated Costigan's accusations against him.