Billy Costigan

**William "Billy" Costigan Jr.** is one of the two titular protagonists (along with Colin Sullivan) of Martin Scorsese's crime drama film, *The Departed*. He is an undercover cop working for the Massachusetts State Police, who goes undercover working for Boston kingpin, Frank Costello.

He was portrayed by Leonardo DiCaprio, who also played Amsterdam Vallon in *Gangs of New York*, Howard Hughes in *The Aviator*, Teddy Daniels in *Shutter Island*, Jordan Belfort in *The Wolf of Wall Street* and Ernest Burkhart in *Killers of the Flower Moon*.

## Biography

### Early life

William M. Costigan Jr. was born on November 7, 1984 in Boston, Massachusetts to William Costigan Sr. and Catherine R. Costigan. Not much is known about Billy's past besides the fact that in school he hit a sport teacher with a folding chair. During Billy's youth, his uncles, Jackie and Tommy both died, with his father himself also dying some point between 1993 and 2005.

### 2006

After Billy's mother dies in 2006, Billy decides to enroll in the Massachusetts State Police, where befriends Trooper Tony Brown. Costigan meets up with Captain Oliver Queenan and Staff Sergeant Sean Dignam, who ask him to work as an undercover cop to get information on Frank Costello, due to Billy's uncle, Jackie having ties to the Costello Crime Family. In order to get Costello and his partner-in-crime, Arnold French's attention, Billy commits various crimes and eventually has to spend time in prison.

### 2007

After Billy is released from prison, he becomes more and more involved in Costello's outfit over the next year. Eventually, Billy's mental health starts to decline while working undercover, and even attempts to quit before he is convinced into staying by Queenan and Dignam. Soon after, Costigan receives a police-appointed psychiatrist, named Madolyn Madden, who he as an affair with and later dates. Later, Billy discovers that Costello is selling stolen computer microprocessors to a Hong Kong Triad, where he then informs this news to the MSP.

Soon after, Costigan finds out that Costello is, in fact, a protected FBI informant, where then informs this news to Queenan and Dignam, as well as the fact that Costello is aware that he has a rat in his operations. Later, Costigan follows Costello to an adult theater, and witnesses Costello giving a man (Sullivan) an envelope containing information of his crew for Sullivan to cross reference with police records. Afterwards, Costigan begins following Sullivan, but after Costigan witnesses Sullivan incidentally kill a restaurant worker, Billy runs off. Soon after, Billy tries to have a meeting with Queenan, but Costigan is informed that he is being followed by Costello's crew. Billy successfully escapes with the help of Queenan, but Queenan is murdered.

After Queenan is murdered, a shootout begins. During the shootout, one of Costello's crew members, Timothy Delahunt, is shot, and after the shootout, informs Costigan that he is aware that Billy is the rat, but then dies from his injuries. Later, Costigan is informed that Costello was murdered by Sullivan, with his assignment now being finished. Costigan, who is unbeknownst to Sullivan's affiliation with Costello, informs Sullivan of his role as an undercover cop in Costello's crew. Soon after, Sullivan leaves the room, and Costigan notices the same envelope from the adult theater and realizes Sullivan's true identity.

Costigan meets up with Sullivan on a rooftop and holds him hostage, as well as calling Trooper Brown, who after also getting up on the rooftop, pulls a gun on Costigan, who ensures his reasoning behind holding Sullivan hostage, but is unsure of what to think. Brown allows Costigan to go down an elevator with Sullivan, where Costigan is murdered by Trooper Barrigan, an officer who is revealed to be another spy working for Costello, after the elevator stops.

## Trivia

* Costigan was based on Chan Wing-yan from the 2002 crime film *Infernal Affairs*, which *The Departed* is a remake of.
* Unlike Costello and Sullivan, Costigan is the only character from the 3 main characters to not be based off a real person.