The Departed (2006) Timeline Explained – Every Event in Order

Billy Costigan was chosen because he had genuine family ties to organized crime, making him credible to infiltrating Costello's mob. The police academy noticed he was intelligent but also had the criminal background that would allow him to blend in with the organization. Captain Queenan and Staff Sergeant Dignam coerced him into going undercover by fabricating an assault charge that sent him to jail, giving him the appearance of a criminal who needed to flip for the mob.

Foreshadowing: Earlier scenes show Costigan being harassed at the police academy, with his superiors questioning whether he's suitable for the job.

• billy costigan
• undercover
• costello
• queenan
• dignam
• police operation

Colin Sullivan became a mole after witnessing Costello's intimidation at a convenience store as a young boy. Costello gave the boy groceries and slyly suggested he could earn more from Costello when he grew up. Sullivan was then recruited as a police officer working directly for Costello, feeding information about police operations to the mob boss while maintaining his cover in the Special Investigations Unit.

Foreshadowing: The opening scene establishes the childhood encounter between young Sullivan and Costello that sets up this relationship.

• colin sullivan
• frank costello
• mole
• informant
• police corruption

While working undercover within Costello's organization, Costigan uncovers evidence that Costello has been secretly working as an FBI informant. This revelation creates a major turning point, as Costigan realizes the man he's been infiltrating has been playing multiple sides all along.

Foreshadowing: Costello's statement about shaping his environment rather than being molded by it hints at his manipulative nature.

• frank costello
• fbi informant
• billy costigan
• revelation
• betrayal

The final confrontation is triggered when Costigan, having learned the truth about both Sullivan being a mole and Costello being an informant, seeks vindication and a return to normal life. Sullivan, who has been trying to identify and eliminate the undercover cop in his unit, faces off with Costigan in a deadly encounter that ends with both men mortally wounded.

Foreshadowing: Throughout the film, both men unknowingly work toward exposing each other while pursuing their own survival.

• billy costigan
• colin sullivan
• final confrontation
• showdown
• death

The rat symbolism in the final shot represents the pervasive betrayal and duplicity that defines the entire narrative. Both Sullivan and Costigan are 'rats', each secretly working against the organization they claim to belong to. The rat scurrying across the Boston skyline serves as a visual metaphor for how betrayal has infected every level of the criminal and police worlds, leaving no one trustworthy.

Foreshadowing: The title itself and multiple references to rats and informers throughout the film build toward this symbolic conclusion.

• rat symbolism
• ending
• betrayal
• metaphor
• boston skyline

Colin Sullivan kills Frank Costello during the climactic confrontation, positioning himself as a hero who took down a notorious mob boss. However, this act is revealed to be part of Sullivan's survival strategy, he eliminates Costello to cover his own tracks as a mole while simultaneously gaining credibility with the police. The killing appears heroic on the surface but serves Sullivan's self-preservation.

Foreshadowing: Sullivan's dual allegiance throughout the film constantly puts him in positions where he must choose between protecting himself or his criminal connections.

• colin sullivan
• frank costello
• killing
• hero
• survival

Madolyn Madden is a psychiatrist who becomes romantically involved with Colin Sullivan while also treating Billy Costigan professionally. This creates a complex love triangle where she unknowingly becomes entangled with both moles. Her relationship with both men represents the personal betrayal that runs throughout the film, as she is completely unaware of their true identities and motivations.

Foreshadowing: The romantic subplot serves to heighten the tension and sense of betrayal rather than provide relief.

• madolyn maddin
• psychiatrist
• love triangle
• affair
• betrayal

Billy Costigan wants to return to normal life after his undercover operation because the job has taken a severe toll on his identity and mental state. Living as a criminal for years, committing violent acts to maintain his cover, has left him psychologically damaged. He seeks vindication and wants to reclaim his true identity as a police officer rather than continue living as a mobster.

Foreshadowing: Costigan's sessions with Madolyn reveal the psychological toll of maintaining his undercover identity.

• billy costigan
• undercover
• identity
• psychological damage
• return to normal life

Captain Queenan is killed by Frank Costello's mob after being exposed as someone who knew about the undercover operation. Staff Sergeant Dignam also meets a violent end as the complex web of betrayal and violence claims lives on both sides of the law. Their deaths underscore the film's bleak portrayal of a world where even law enforcement figures cannot escape the violence spawned by corruption and deception.

Foreshadowing: The escalating violence throughout the film creates an atmosphere where no character is safe.

• captain queenan
• staff sergeant dignam
• death
• violence
• betrayal

The opening convenience store scene establishes the formative relationship between young Colin Sullivan and Frank Costello. Young Sullivan witnesses Costello's intimidation tactics firsthand, and Costello takes an interest in the boy, giving him groceries and suggesting future employment. This moment plants the seed for Sullivan's role as a mole, showing how Costello cultivates future informants from a young age.

Foreshadowing: This childhood encounter directly leads to Sullivan becoming Costello's eyes and ears within the police department.

• convenience store
• young colin sullivan
• frank costello
• childhood
• origin story

Colin Sullivan's downfall is orchestrated by his own survival tactics. After killing Costello and attempting to eliminate Costigan, Sullivan manipulates events to position himself as a hero. However, his own machinations and the accumulating evidence of his double-cross eventually catch up with him. His obsession with self-preservation and willingness to betray everyone around him ultimately ensnares him in a fate he cannot escape.

Foreshadowing: Sullivan's pattern of betrayal throughout the film builds toward his inevitable downfall.

• colin sullivan
• downfall
• survival tactics
• betrayal
• consequences

The film opens with historical footage of Boston riots to establish the historical context of violence and social tension in the city. This backdrop illustrates the societal issues that influence the characters' actions throughout the film, showing that the corruption and conflict depicted in the narrative are deeply rooted in Boston's history. The footage also sets the tone for the brutal, uncompromising world the characters inhabit.

Foreshadowing: The historical context establishes that the violence and corruption depicted are part of a longer, darker history.

• boston riots
• historical footage
• opening scene
• context
• violence