Leonardo DiCaprio described his character as being in a "constant, 24-hour panic attack."

Leonardo DiCaprio called his one-on-one scene with Jack Nicholson "one of the most memorable moments of my life."

When the film won the Oscar for Best Picture, Martin Scorsese said that he was surprised the film had won. Scorsese said that because the film is such a tough, nasty, and violent film, he never thought about the idea of awards while he was filming it.

Martin Scorsese really wanted Al Pacino for the role of Costello, because he had never worked with Pacino before, but he turned it down. Jack Nicholson was Scorsese's second choice. Pacino would later go on to appear in Scorsese's The Irishman (2019).

Originally, Jack Nicholson turned down his role in the movie, but after a meeting with Martin Scorsese, William Monahan, and Leonardo DiCaprio, he was finally convinced to play the role of Frank Costello. The main reason he joined the production was because he had previously done a few comedies, and wanted to play a villain again, and he considered the character of Costello to be the ultimate incarnation of evil.

Mark Wahlberg easily fell back on his native accent. Martin Scorsese joked it was so thick, they'd need subtitles.

Roughly half of the $90 million budget went to the actors' salaries.

When receiving the top award from the Director's Guild of America for this film, Martin Scorsese said that this "is the first movie I have ever done with a plot."

Vera Farmiga met with a real LAPD psychiatrist to prepare for her role. The psychiatrist read the script, and told Farmiga that Madolyn did pretty much everything wrong.

According to Ray Winstone, he and Jack Nicholson did not get along with each other while filming.

The first remake of a foreign film to win an Academy Award for Best Picture. The second one is "CODA" (2021)

Martin Scorsese did not realize this was a remake of a Hong Kong movie until after he had agreed to direct it.

When Frank (Jack Nicholson) walks off with the angel kids, the yacht in the background is the same yacht Jordan Belfort (Leonardo DiCaprio) owns in The Wolf of Wall Street (2013).

Leonardo DiCaprio visited Boston, and met with people tied to the Irish Mob.

Martin Scorsese wanted to shoot the film in Boston, where the story is set. The bulk of the film was shot in New York, partly due to concerns about setting up production and politics, partly because of New York's 15% filmmaking tax credit. They shot in Boston for 3 weeks in June and 3 more in August. After the success of this film, Massachusetts created a 25% tax credit for filmmaking.

A possible reason why Leonardo DiCaprio did not receive an Oscar nomination for his performance in this movie was because Warner Brothers initially did not want to favor DiCaprio over his co-stars, and place him in the leading actor category. The studio favored DiCaprio's leading performance in Blood Diamond (2006), which eventually got him a nomination. DiCaprio refused to campaign against his male co-stars in the supporting actor category, so Warner bought no supporting actor ads for DiCaprio, and he did not receive a nomination.

Matt Damon decided his character should be impotent to counter Frank's macho personality.

According to Martin Scorsese, the film was envisioned as a low-budget production, but the budget increased as more stars became attached.

After Jack Nicholson joined the cast, his character was re-written to give him a bigger part.

Martin Scorsese deliberately chose not to watch Infernal Affairs (2002), the original that this was based on, until after he'd completed this film.

Martin Sheen was one of the last actors cast. The reason why he agreed to appear in the film was because he wanted to work with Martin Scorsese.

Originally, Brad Pitt was cast as Colin Sullivan, but later dropped out to work with Alejandro G. Iñárritu in Babel (2006). He continued to produce the film under his (and his then wife Jennifer Aniston's) production company, Plan B.

As research for his character's occupation, Matt Damon worked with a Massachusetts State Police unit out of Boston. He accompanied them on routine patrols, participated in a drug raid, and was taught proper police procedures, like how to pat down a suspect.

Ray Liotta was the original choice for the role of Dignam, but had to reluctantly decline, due to other commitments.

This marks the third time that Martin Scorsese has used The Rolling Stones' "Gimme Shelter" in one of his films. It also appeared in Goodfellas (1990) and Casino (1995).

Leonardo DiCaprio gained fifteen pounds of muscle for his role as Billy Costigan.

Jack Nicholson refused to wear a Boston Red Sox hat during filming, and instead wore his New York Yankees hat.

In the scene when Leonardo DiCaprio is at the airport, the little girl that is seen with the pink backpack is Martin Scorsese's daughter Francesca.

Martin Scorsese put the finishing touches on this film a week before its theatrical release.

The third most worldwide commercially successful film of Martin Scorsese's career.

After completing The Aviator (2004), Martin Scorsese kept Alec Baldwin in mind for future collaboration and ultimately decided to cast him in the role of Ellerby, which was offered to Mel Gibson first, but Gibson was unable to accept the part, because he was starting production on Apocalypto (2006) at the time.

Martin Scorsese joked that he's much more comfortable with gangsters on-set than police. "I was worried that there were cops all around me and they were going to take me in."

Leonardo DiCaprio was cast in the title role in The Good Shepherd (2006), but he dropped out to play Billy Costigan in this movie. Matt Damon then took the role. Robert De Niro turned down the role of Queenan to appear in The Good Shepherd (2006).

Leonardo DiCaprio called Billy and Colin "two sides of the same coin".

Screenwriter William Monahan envisioned a sequel to the film, citing that it would've focused on overlooked aspects of the first film, such as political corruption. Monahan had watched the sequels to the original film on which this movie was based, but felt that a potential sequel would've gone in a different direction set by this film. Mark Wahlberg also indicated that Dignam would've been the main character in this film. To date, plans for the sequel haven't materialized.

The first teaming of Jack Nicholson and Martin Scorsese.

Originally, this remake was planned with Brad Pitt as Colin Sullivan, and Tom Cruise as Billy Costigan.

Colin Sullivan's apartment does not exist. The view of the Massachusetts State House was an effects shot from the roof of Suffolk University, which is the law school where Sullivan says he is taking night classes. Cinematographer Michael Ballhaus evaluated the shot during pre-production.

(At around one hour and seventeen minutes) It was Jack Nicholson's idea to film the scene when Frank Costello attends the opera. It was also Nicholson's idea to have one black woman and one white woman in the scene with him.

Martin Sheen and Leonardo DiCaprio rode the Red Line about one hundred times to get enough takes of one sequence.

When Colin has dinner with Madolyn, he states, "What Freud said about the Irish is we're the only people impervious to psychoanalysis." According to the FAQ section of the Freud Museum in London, Sigmund Freud, "There is no evidence Freud said the quote. The only documentation seems to be Anthony Burgess, in his introduction to a book of Irish short stories: 'One of Freud's followers split up human psychology into two categories, Irish and non-Irish.'"

There are two phone numbers used in the film. The first is Billy's phone number, which is 617-869-1469 (It appears when Colin Sullivan answers the phone). This is a real Boston number used by Sprint Spectrum. If someone calls it, you will get a generic voicemail box, which is full. The other number is 311-555-2368, which was a phone number used in telephone company publications.

Vera Farmiga was nervous about meeting Leonardo DiCaprio and Martin Scorsese. "You expect there to be a certain chasm between you and them, and there wasn't."

Martin Scorsese had originally wanted to cast a known actress, either Kate Winslet, Emily Blunt, Hilary Swank, or Jennifer Aniston, for the part of Madolyn.

Martin Scorsese agreed to direct this movie because it reminded him of White Heat (1949), a film noir starring James Cagney, also about an undercover officer embedded with a charismatic gangster.

Warner Brothers bought the remake rights to Infernal Affairs (2002) for $1.75 million in 2003.

The real mob boss Frank Costello was a contemporary of Lucky Luciano and Meyer Lansky in New York City.

Martin Scorsese wanted Matt Damon to play Sullivan because he had a "cocky attitude, a bravado."

(At around one hour and fifty-five minutes) The newscaster seen reporting the news story detailing the dumped body by Costello's gang was a real Boston area newscaster at the time of filming. He reported for Boston's Warner Brothers affiliate station WB56.

Composer Howard Shore said Martin Scorsese wanted the music score to be a tango, to portray the nature of the deadly game being played by the characters.

At the beginning, when the main characters are in a police academy ballistics lecture, the large flip chart illustrations seen in the background are Warren Commission exhibits of President John F. Kennedy's head wounds, prepared by medical illustrator H.A. Rydberg under the direction of Dr. James Humes, the chief examiner of Kennedy's autopsy. Texas Governor John Connally was also riding in the car that day, and was also shot. John Connolly is also the name of the FBI agent who recruited Whitey Bulger as an informant, and ultimately protected him from investigation or prosecution for many years.

The "f" word, and its derivatives, are used two hundred thirty-eight times.

Martin Scorsese said that he made this film to honor crime genre directors such as Robert Aldrich, Samuel Fuller, and Don Siegel.

Thomas B. Duffy is a retired Massachusetts State Police Major, who worked out of Boston for nearly thirty years, and specialized in organized crime. He was particularly involved in the case against notorious South Boston mob boss James "Whitey" Bulger, on whom Frank Costello is partly based. Duffy appears as the Governor, who delivers a speech to the graduating police cadets. There was an unconfirmed sighting of Bulger, one of the F.B.I.'s Ten Most Wanted, at a theater showing the film by a Deputy Sheriff in San Diego, California. Bulger was captured in Santa Monica, California on June 22, 2011. He'd been living in an apartment complex just a few blocks away from the production offices of GK Films (U.S.), who produced Edge of Darkness (2010), in which Duffy also appeared.

Vera Farmiga's character is a composite of two characters from the original Infernal Affairs (2002).

(At around twenty-one minutes) Cousin Sean (Kevin Corrigan) makes a disparaging comment about Puerto Ricans. In real-life, Corrigan is partially of Puerto Rican descent.

Denis Leary was offered the role of Dignam in this film, but turned it down due to scheduling conflicts with his television show, Rescue Me (2004). He was disappointed, but he did hold Mark Wahlberg's performance in high regard.

The first Best Picture Oscar winner of the twenty-first century that wasn't released on VHS in the United States, and the first to be released on the short-lived HDDVD format. Warner Brothers Home Entertainment had already phased out VHS by 2006, therefore, the film was initially released on DVD, Blu-ray, and HDDVD the following year.

This marks the second Martin Scorsese film in which Leonardo DiCaprio plays a young Irish man who infiltrates the ranks of a menacing gangster. The first being Gangs of New York (2002).

On the DVD commentary for Gone Baby Gone (2007), Ben Affleck says that Jay Giannone, who has small roles in both films, was also the Boston accent coach for Leonardo DiCaprio in this movie.

Martin Scorsese directed Mark Wahlberg to his first Oscar nomination, for his role of Dignam. He was later nominated for The Fighter (2010) for Best Picture.

Martin Scorsese won Best Picture and Best Director Oscars over Clint Eastwood nominated for Letters from Iwo Jima (2006). The two competed two years earlier when Scorsese was nominated in both categories for The Aviator (2004) and Eastwood winning both Oscars for Million Dollar Baby (2004).

(At around thirteen minutes) When Queenan and Dignam are interviewing Costigan, Costigan says "Families are always rising and falling in America." Queenan wants to know who said that, and it turns out to be Nathaniel Hawthorne. Dignam quips, "What's the matter smart ass, don't know any f****n' Shakespeare?" Later (at around one hour and one minute), as Queenan hands the clipboard to Sullivan, it is Queenan who quotes William Shakespeare with "the readiness is all", from Hamlet's "Fall of a sparrow speech," Act V, scene II.

Frank Costello (Jack Nicholson) was supposed to wear a Red Sox cap in the movie, but refused to. The hatred of Boston sports teams date back to the days of Nicholson's love affair with the Lakers and the heated rivalry with the Celtics. The Red Sox cap was the signature uniform of James "Whitey" Bulger, but Nicholson couldn't overcome his disfavor.

The roles of the Triad Boss and his translator were originally intended as cameo appearances for Andy Lau and Tony Chiu-Wai Leung, the stars of the original Infernal Affairs (2002).

(At around forty-nine minutes) When Colin (Matt Damon) tells Fitzgibbons (David O'Hara) to call his mother from Trooper Brown's phone, the ringtone on the receiving phone is "Scotland the Brave", one of the tunes played on the bagpipes at the cadets' graduation ceremony.

The film cast includes three Oscar winners: Jack Nicholson, Leonardo DiCaprio, and Matt Damon; and three Oscar nominees: Mark Wahlberg, Alec Baldwin, and Vera Farmiga.

(At around one hour and seventeen minutes) Frank Costello attended the Gaetano Donizetti opera Lucia di Lammermoor. This is a musical homage to Scarface (1932), as Paul Muni's character would often whistle the sextet from this opera, whenever he killed someone.

RZA was offered Anthony Anderson's role, but turned it down because of scheduling conflicts.

(At around nineteen minutes) Tom Kemp and Zachary Pauliks appeared in a flashback scene, in which Frank talks to Billy's father, as young Billy looks on. Although the scene was deleted, the actors appear in the picture that Billy gives to his aunt, and the actors are still listed in the closing credits.

The only film directed by Martin Scorsese to win Best Picture at the Academy Awards.

(At around one hour and ten minutes) The movie playing in the background at Sullivan's house is Audition (1999).

Ethan Hawke was considered for the role of Sergeant Dignam.

Near the end Frank resents that he never had an heir, a son of his own. Earlier, this was foreshadowed as we see Gwen reading a book about trying to get pregnant.

One of three Best Picture Oscar winners featuring Jack Nicholson. The other two are One Flew Over the Cuckoo's Nest (1975) and Terms of Endearment (1983). Interestingly, it's the only one of the three where he didn't win, nor was nominated for an Oscar.

Fifty minutes longer than the original, Infernal Affairs (2002).

This was the last Martin Scorsese film shot by cinematographer Michael Ballhaus.

The first Warner Brothers Best Picture Oscar winner without Morgan Freeman co-starring since Amadeus (1984). The Best Picture winners in between those from the studio are Driving Miss Daisy (1989), Unforgiven (1992), and Million Dollar Baby (2004).

(At around three minutes) The comic book that Frank Costello gives young Colin Sullivan in the beginning of the movie is Issue #11 of the "Wolverine" series, which was published in September 1989.

While shooting on-location in Boston, Massachusetts, Martin Scorsese viewed the film's dailies at Emerson College.

(At around two hours and five minutes) According to his file, Billy Costigan's birth date is November 7, 1984. Although a second shot of the same screen then labels it as November 7, 1980.

This is the first time Martin Scorsese and Jack Nicholson worked together. They first met twenty-eight years earlier on the set of Scorsese's documentary The Last Waltz (1978).

This was one of Martin Scorsese's few "present day" films, as most of his films take place in the past. Except for Taxi Driver, Mean Streets, Alice Doesn't Live Here Anymore, The King of Comedy, Cape Fear, Stones Scorsese Shine A Light, George Harrison Living in the Material World, After Hours, New York Stories, the Color of Money, Bob Dylan No Direction Home, Who's That Knocking at My Door and Michael Jackson's Bad.

Peter Mullan was cast in the film, but ended up dropping out. Mullan said, "I was not in the right frame of mind. I was exhausted, and I would not have done a good job. It would've been pointless."

Vera Farmiga's scenes were filmed at the end of the schedule.

Vera Farmiga was one of the only actresses who didn't watch Infernal Affairs (2002), the movie on which this is based. Madolyn is inspired by multiple characters, so Farmiga thought it would be confusing for her.

The funeral scene was filmed at Green-Wood Cemetery in Brooklyn, New York. Martin Scorsese also shot Gangs of New York (2002) there.

1997 was a significant year for the four main actors of this film. Leonardo DiCaprio starred in Titanic (1997), which would go on to become the second highest grossing movie of all time, and win eleven Academy Awards. Matt Damon won an Academy Award for Best Original Screenplay, and got a Best Actor nod for Good Will Hunting (1997). He was beaten for Best Actor by Jack Nicholson for As Good as It Gets (1997). Lastly, Mark Wahlberg stepped into the limelight in the critically acclaimed Boogie Nights (1997).

Matt Damon and Andy Lau (the mole in the original Chinese film) appeared in The Great Wall (2016).

Mark Wahlberg turned down his role in The Departed multiple times. He finally changed his mind after Martin Scorsese convinced and persuaded him more than once to star in the film.

Leonardo DiCaprio and Martin Sheen appeared in Catch Me If You Can (2002).

Jack Nicholson says he joined the cast because he was looking for a "nice juicy bad guy to play.". Not exactly a stretch. Nicholson usually plays bad or crazy guys. (The Shining, One Flew Over the Cukoo's Nest, Batman, As Good As It Gets, The Witches of Eastwick, Little Shop of Horrors, etc.)

(At around two hours and five minutes) When Sullivan looks up Costigan's information on the computer, the computer is a PC, but the graphical interface is actually a Mac.

Screenwriter William Monahan has stated that Sergeant Dignam's first name is Sean.

To accommodate his schedule, Mark Wahlberg had shot his scenes at the beginning of production.

Frank wears a Notre Dame Fighting Irish t-shirt. That's where Queenan says his son goes to school.

(At around one hour and two minutes) During the exchange with the Chinese gangsters, Sullivan sends a text message to Costello saying that all cell phone calls are being monitored. The number dialed by Sullivan is a real Boston area code (617).

Martin Sheen based his character on Thomas B. Duffy.

The classroom scene, police academy graduation scene, and shooting range scene (all at the beginning of the film) were shot near the end of production. Historic Ft. Schuyler on the campus of State University of New York's Maritime College was the backdrop.

In Turkey, there is a television series based on this film, Içerde (2016), which means "Inside".

Whenever the song "Sweet Dreams" by Patsy Cline is heard, it is usually in a scene with Jack Nicholson.

Included among the "1001 Movies You Must See Before You Die", edited by Steven Schneider.

Warner Brothers and the producers of this movie wanted the running time of the film to be two hours and twenty minutes. The running time ultimately came to be two hours and thirty-one minutes.

The only movie jack Nicholson has been in that won best picture that won no Oscars for acting.

Steven Spielberg said that he and Martin Scorsese were going to have a Q and A with each other to talk about the film. However, it never happened.

When Bill is watching TV he's watching the end of the movie The Informer (1935), which is about an Irishman who "rats" on his friend.

Lyrics from the Alice Cooper song School's Out are referenced at least twice in the dialogue: once by Frank Costello ("No more pencils, no more books.") and once by William Costigan ("School's out.")

Tyler Perry publicly expressed interest in playing the role that went to Anthony Anderson.

Mark Wahlberg and screenwriter William Monahan met to discuss potential projects when talk of a sequel came up. Monahan envisioned the story revolving around Dignan before, during and after the events of the film with producer Brad Pitt and Robert DeNiro costarring. According to Wahlberg, he and Monahan went to pitch it to the studio but they declined, given Monahan didn't have a synopsis and had a distaste for that and pitching to a studio.

Mark Wahlberg and Leonardo DiCaprio appeared in The Basketball Diaries (1995).

The "MASS Processor Company's" microprocessor, shown in the movie, is really an ST Microelectronics' ST9F150JDV1QC micro-controller, released in 2003 and intended for applications such as MP3 players, GPS devices, and car radios. It went for around seven dollars at the time it was released (in the movie it is stated they go for one hundred thousand dollars each). The microprocessor has an internal clock frequency of twenty-four Megahertz and one hundred pins, and can hold up to four Megabytes of memory. A typical Intel Core 2 Duo microprocessor, released in 2006 (the same year as The Departed) for use in desktop computers, runs at 1,400 Megahertz or higher frequencies, has 775 pins, and can address up to four thousand Megabytes.

(At around twenty-eight minutes) When Madolyn meets Colin in the elevator, she gives Colin her business card. The logo of the American Psychological Association is clearly visible on it.

Due to fast and dynamic editing style, some of the whip zooms and longer dolly moves by cinematographer Michael Ballhaus were trimmed from the movie. This includes his signature 360-degree dolly shot on a secret rooftop meeting between Billy and Queenan.

Gerard McSorley was originally slated to play Queenan, but had to drop out of the project.

Second Best Picture Winner for both Leonardo DiCaprio and Martin Sheen. They previously appeared in Titanic (1997) and Gandhi (1982), respectively. Both films featured Bernard Hill in a supporting role. They previously appeared together in Catch Me If You Can (2002) for director Steven Spielberg, who won Best Picture and Best Director for Schindler's List (1993), which featured Gandhi (1982) cast member Ben Kingsley. This is also composer Howard Shore's third Best Picture winner, after The Silence of the Lambs (1991) and The Lord of the Rings: The Return of the King (2003), the latter of which also featured Hill.

Mark Wahlberg, who plays Dignam, later went on to executive produce Boardwalk Empire (2010) alongside Martin Scorsese.

Vera Farmiga starred in Orphan (2009), produced by Leonardo DiCaprio.

The microprocessor acts as a McGuffin, a device which only serves merely as a trigger for the plot, as per Hitchcock's definition.

Chris Messina met with Martin Scorsese to discuss taking on one of the roles in the film.

As of May 2020, this is the last film to feature Jack Nicholson that grossed over $100 million at the North American box office.

Captain Queenan mentions to Billy Costigan that his son attends Notre Dame. Martin Sheen's character from The West Wing (1999), President Josiah Bartlet, went to the same university, and was also a fan of the Boston Celtics.

The only Best Picture nominee that year to be also nominated for Best Adapted Screenplay, the other four were nominated in the Original Screenplay category.

Matt Damon and Alec Baldwin appeared in The Good Shepherd (2006) and on 30 Rock (2006).

If you listen closely in some scenes you can hear the music used later in Rizzoli & Isles (2010) in the background.

This film is in the Official Top 250 Narrative Feature Films on Letterboxd.

The scene where Matt Damon plays rugby against the fire department he plays in the position Flanker. In 2009 he portrays Francois Pienaar in the movie Invictus who also played flanker for the South African Rugby team in the 1995 Rugby World Cup movie directed by Clint Eastwood

Jill Brown's debut.

Sallie Toussaint's debut.

The song "Comfortably Numb" by Pink Floyd (this version sung by Irishman, Van Morrison) is featured in this film, which also features actress Vera Farmiga. Pink Floyd's album "The Wall" contains a song entitled "Vera."

During the scene where Mr. French (Ray Winstone) is throwing firecrackers, the song Baby Blue by Badfinger can be heard in the background. This song was also used in the final scene of the television series Breaking Bad (2008).

The police chief played by Alec Baldwin says that a wedding ring "lets people know you're not a homo", but gay marriage was already established in the state of Massachusetts when the movie was released. However, in the mind of a conservative policeman, marriage would likely mean to a submissive woman.

Armen Garo, who plays one of the ill-fated Providence gangsters, plays a Providence gangster again in Vault (2019).

After the rugby game during the state police training sequence, Sullivan quips an insult about firemen to Barrigan, played by James Badge Dale. James Badge Dale would play a fireman in 2017's "Only The Brave."

Desiree April Connolly's debut.

Thomas B. Duffy: the Governor of Massachusetts, swearing in the new Police Academy graduates.

Graham King: (At around twelve minutes) The producer of the film appears in photographs as the deceased Jackie Costigan.

(At around one hour and seventeen minutes) The scene where Frank Costello throws cocaine on hookers was one of many bizarre ideas contributed by Jack Nicholson, who also suggested wearing a strap-on for the scene with Matt Damon in the porn theater.

Many scenes with Jack Nicholson were improvised. Nicholson was given the opportunity to do whatever he wanted to add to the character's unpredictability. The scene where Billy and Frank are talking was loosely scripted, and many surprises happened in it, including Frank pulling out the gun.

Though there was a real mobster named Frank Costello, this film's character is loosely based on James "Whitey" Bulger, who ran a Boston-based Irish gang while working as an FBI informant, protecting him from prosecution while he killed dozens of people. His FBI handler was convicted of multiple felonies.

DIRECTOR TRADEMARK (reference): When Sullivan turns on the shower before Madolyn starts to listen to Costigan's tape, the shots are the same three shots in Psycho (1960)'s infamous shower scene.

Throughout the film, Martin Scorsese used Xs mostly shown in the background to mark characters for death. Examples include shots of Costigan walking through the airport while talking to Sergeant Dignam, Queenan falling to his death (on the building's glass windows as Queenan falls to the ground), and Sullivan in his office discussing the flow of information with Costello (the X is created by the light shining through the window). This is an homage to Scarface (1932).

Neither of the leaders on either side (Queenan from the state police force and Frank Costello from the mob syndicate) discovers the identity of the infiltrators in their own side.

At the end of the movie when Billy brings the tape to Madolyn, we can deduce that the child is not from Colin Sullivan, but from Costigan. She wants to tell him something, but he leaves right before she does. Sullivan also has, during a scene in the film, some "issues with what happened last night". Madolyn then sleeps with Billy.

At the beginning of the film, Frank Costello instructs the store clerk to fill a brown paper bag with various groceries for the kid Colin Sullivan, notably a couple of loaves of bread and a couple of quarts of milk. In the last scene of the film, we see adult Colin Sullivan walking into his apartment with a paper bag full of groceries, two of the items you can see in the bag during this scene are a couple of loaves of bread and a couple of quarts of milk.

Body count: twenty-two.

The rat at the end is completely digital.

Martin Scorsese expresses the highly unpleasant experience in making the film. He states, "Moral Ground Zero, I call it, all the characters killed at the end, basically everyone, and there was no place to go, after that. You know, I hardly did any press for that film. I was tired of it. I felt it was maddening. I mean, I like the picture," he continues, "but the process of making it, particularly in the post-production, was highly unpleasant. I don't care how much I'm being paid, it'll kill me. I'll die. Very simply."

(At around five minutes) Right after the time skip in the beginning of the movie, during the first lesson at the police academy, the teacher is elaborating on the details of a gunshot wound to the head, which is the leading cause of the vast majority of deaths throughout the course of the rest of the movie.

When Billy Costigan interrogates the drug-addicted bank robber (Joseph Riccobene), who reveals to him that Frank Costello is an FBI informant, the television set in the bank robber's living room is playing the final scene from The Informer (1935). The movie has a similar plot, about an Irish nationalist, Gypo Nolan (played by Victor McLaglen in an Oscar winning role), who turns informant, and feels guilty after betraying a friend to the Irish "Black and Tan" police force.

At the beginning of the film, Frank Costello meets young Colin Sullivan while collecting money from a local convenience store. Later, Billy Costigan attacks 2 men from Providence at the same store.

(At around two hours and ten minutes) The CD that Costigan mails to Colin is mailed in the cover for The Rolling Stones' album "Exile on Main St." Earlier in the film (at around thirty-six minutes), when Costello beats Costigan's hand with his own shoe, a song from the album, "Let It Loose", plays over the scene.

Every time an X shape appears in a scene, someone dies.

Of the five movies that Martin Scorsese and Leonardo DiCaprio have collaborated on, this is the only one in which DiCaprio's character dies.

(At around two hours and twenty minutes) In the final scene, as Sullivan walks to his apartment, the floor has large patterned Xs on the carpet. He walks over two of them as he approaches the door. It's as if to say strike one, strike two, and strike three being the coup de grace from Dignam.

The picture of the CD from William Costigan (Leonardo DiCaprio) that Madolyn (Vera Farmiga) listens to is the cover of the 1972 The Rolling Stones' album "Exile on Main St."

When Sullivan is killed at the end by Dignam, his blood is shaped like the number 19.

Nicholson's laugh moments before his death, with blood around his face, reminds the viewer of another iconic character, namely DCU's The Joker.