While The Departed may not be Martin Scorsese’s most popular film, it still has plenty of merit. It’s fast-paced, it’s shot beautifully, the performances by the cast are riveting, and the plot is brilliantly complex. It’s a cat-and-mouse thriller told from two different perspectives.

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While one Boston cop works with a local crime boss to leak police information, another Boston cop goes undercover and infiltrates that same crime boss’ organization. The movie’s two protagonists ⁠— played powerfully by Leonardo DiCaprio and Matt Damon ⁠— are both searching for each other, and only we hold all the information. Here are 10 Behind-The-Scenes Facts About The Departed.

Martin Scorsese didn’t realize it was a remake when he signed on

Leonardo DiCaprio and Matt Damon on a roof in The Departed

The Departed is an American remake of a Hong Kong crime thriller called Infernal Affairs, but when Martin Scorsese signed on to direct it, he didn’t realize it was a remake. He was still putting the finishing touches on his final cut just a week before the film’s release.

When he accepted the Director’s Guild of America’s top award for directing this movie, Scorsese joked that it was the first movie he ever made that actually had a plot. So far, The Departed is the only remake of an international movie ⁠— and the only movie helmed by Scorsese ⁠— to win the Academy Award for Best Picture.

Al Pacino was the top choice to play Frank Costello

Al Pacino in court in The Irishman

Ever since meeting him in the ‘70s, Martin Scorsese had wanted to work with Al Pacino. The actor was Scorsese’s first choice for the role of Frank Costello in The Departed, but he turned it down. Jack Nicholson was the director’s second choice, and he accepted the part because he’d just starred in a few comedies and he was eager to play a sinister villain in a darkly themed drama.

However, it took some convincing from Scorsese, Leonardo DiCaprio, and screenwriter William Monahan before Nicholson signed on. Scorsese and Pacino would end up working together on the partially fictionalized crime epic The Irishman.

Mark Wahlberg based his performance on real cops who’d arrested him

Mark Wahlberg and Matt Damon in The Departed

Martin Scorsese had to offer Mark Wahlberg the role of Sgt. Dignam a few times before he accepted it. Before Wahlberg signed on, a few other actors were considered. Ethan Hawke was considered, and Ray Liotta had to turn it down due to scheduling conflicts. Denis Leary couldn’t take the part because it conflicted with filming for his TV series Rescue Me, and he’s said that he enjoyed Wahlberg’s performance in the film.

Wahlberg based his performance on real cops who’d arrested him, along with his parents’ shocked reactions when they had to bail him out with their grocery money.

Frank Costello was influenced by Whitey Bulger

Frank has a chat with one of his moles in The Departed

Frank Costello is a fictional character, but he was heavily influenced by James “Whitey” Bulger, an infamous criminal who ran an Irish mob out of Boston while secretly informing the FBI about his business. This kept him protected from prosecution while he was murdering dozens of people. His handler at the Bureau was later convicted of a number of felonies.

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Bulger’s informant work with the FBI inspired the big twist in The Departed. Johnny Depp played Bulger in a 2015 biopic called Black Mass, directed by Scott Cooper. In 2018, Bulger was murdered in prison at the age of 89.

Half of the $90 million budget was spent on actors’ salaries

Jack Nicholson and Leonardo DiCaprio in The Departed

According to Martin Scorsese, The Departed was conceived as a low-budget production. However, as more and more big-name actors signed on ⁠— Leonardo DiCaprio, Matt Damon, Jack Nicholson, Mark Wahlberg, Alec Baldwin, Martin Sheen etc. ⁠— the budget ballooned to a whopping $90 million. This isn’t quite as much as, say, a Star Wars movie costs, but it’s a lot for a crime movie.

About half of this budget was spent on the actors’ salaries alone. When the movie first went into development, Colin Sullivan was going to be played by Brad Pitt (who ended up just producing) and Billy Costigan was going to be played by Tom Cruise.

Jack Nicholson refused to wear a Red Sox cap in the film

Leonardo DiCaprio and Jack Nicholson in The Departed

Whitey Bulger, the real-life criminal figure who inspired the character of Frank Costello, was known to wear a Boston Red Sox cap as part of his everyday attire. So, Costello was supposed to wear one. However, Jack Nicholson refused to wear a Red Sox cap, having hated the Boston sports teams since the Celtics-Lakers rivalry.

Instead, Nicholson wore his own New York Yankees cap in the movie. The hat thing was a minor on-set difficulty compared to some of the others. Ray Winstone claims that he didn’t get along with Nicholson on the set of The Departed, despite the close friendship shared by their characters.

Jennifer Aniston, Emily Blunt, and Kate Winslet were considered for the role of Madolyn

Madolyn with Colin in The Departed

When The Departed was being made, Vera Farmiga wasn’t a known movie star, and a name star is what Martin Scorsese originally wanted for Farmiga’s role, the police psychiatrist Madolyn. Actors considered for the part included Jennifer Aniston, Emily Blunt, Kate Winslet, and Hilary Swank. In her preparation for the role after being cast, Farmiga met with a real LAPD psychiatrist, who took a look at the script and determined that pretty much everything Madolyn did was wrong.

Farmiga is one of the few cast members who didn’t watch Infernal Affairs, the movie on which The Departed was based, because her character in the remake was a composite of two characters from the original and she thought it would just confuse things.

Matt Damon worked with real Boston police officers in preparation for his role

Colin Sullivan in The Departed

In his research for the role of Colin Sullivan in The Departed, Matt Damon worked with a real Massachusetts State Police unit operating in Boston. He went for ride-alongs with the cops on routine patrols of the city and even took part in a drug bust. The unit also taught Damon how to properly carry out police procedures, like patting down a suspect, so that his performance would be more authentic.

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It was Damon’s own idea for his character to be impotent, as he thought it would counteract with his boss Frank Costello’s overtly masculine characterization in an interesting way.

Jack Nicholson suggested some of Frank Costello’s weirdest quirks

The Departed Cropped

Jack Nicholson had a lot of fun playing Frank Costello in The Departed. He wanted to play Frank as the embodiment of evil, and he improvised a lot of his scenes to add to the character’s unpredictable nature.

The scene in which he sits down with Billy ⁠— which Leonardo DiCaprio has called a high point in his career ⁠— was very loosely scripted. Frank pulling out a gun was one of Nicholson’s most surprising improvisations. Nicholson also came up with a lot of Frank’s most outlandish quirks, like throwing cocaine on prostitutes and wearing a strap-on for the scene in the porno theater.

A sequel focused on Dignam almost happened

Dignam-Departed-Mark-Wahlberg

After The Departed became a box office hit, screenwriter William Monahan came up with an idea for a sequel that would’ve focused on Sgt. Dignam. Monahan wanted to cover some sociopolitical subject matter that he overlooked in the original, like corruption in the local government. At one point, Robert De Niro was being courted to play a U.S. Senator (though it’s unclear how far these talks progressed).

Although Infernal Affairs, the movie on which The Departed was based, has a handful of sequels, Monahan planned to take his sequel in a different direction. For whatever reason, the sequel never came to fruition.

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