Continuity mistake: When Ellerby attacks the guy for not installing the cameras in the right place, he knocks off a map from the board. A second later Ellerby is still going after him, and the map is fixed.
Continuity mistake: In the scene after Queenan dies, when Sullivan picks up his phone to contact Costigan, he presses the "talk" button and a smudge of blood is left. In subsequent shots, there's no trace of blood on the "talk" button. (01:49:45)
Other mistake: When Costigan drags a handcuffed Sullivan into the elevator, Costigan slams Sullivan against the wall and his left arm is visible and not in handcuffs. (02:13:05)
Revealing mistake: When Costello's men drive off, after throwing Queenan off the top of the building, the state troopers are firing at the van. One back window is shot out, then in the next shot of the van the other window is shot out and then the same one is shot again so the one window is shot out twice in the same scene.
Revealing mistake: ***SPOILER*** When Costello is killed, a blood-pack is noticeable under his shirt.
Continuity mistake: When Billy Costigan is at the funeral near the beginning of the movie and reads the card signed "From Frank Costello," it is initially seen as a heavy bold script, but in the closeup, it is a thin script written in different handwriting.
Continuity mistake: When young Sullivan is at Mass, a priest is swinging the smoking incense burning. In the next shot the smoke is gone, and he is away, arriving with the burner and repeating the previous movement.
Continuity mistake: When Costigan is with Madolyn in her office, the tissues in the tissue box change consistently between shots.
Continuity mistake: At Billy's mother's funeral, the signature of Frank Costello on the flowers changes between shots.
Continuity mistake: When Billy and Frank are sitting in a bar, Billy is just sitting at the table. In the next shot he's suddenly in the middle of blowing smoke rings into the air.
Continuity mistake: While Costigan is having coffee with Madolyn, a coffee cup suddenly appears in his hands close to his mouth, and the toothpick that was in his mouth a second ago vanishes.
Continuity mistake: In the scene where Alec Baldwin is briefing the cops on the micro processor bust, his shirt has distinct sweat patterns. These patterns change between scenes, back to original then finally almost dry. (00:59:55)
Visible crew/equipment: When the song starts, right before the main title, we have a dolly shot of Billy in jail. It starts from a red wall and moves towards him. If you look closely at the wall, you can see the subtle shadow of the camera and the rest of the equipment as it moves.
Continuity mistake: The top layer on their dessert changes when Sullivan and Madolyn are in the restaurant. Between shots, the top piece changes back and forth between flat and curved.
Continuity mistake: When Costello and French encounter the cops, the first shot shows the cops' car turning their lights on. In a new shot a second afterwards the lights on the middle and right side cars are out and they are turning them on again. On yet another new angle, the lights on the car on the left turn from off and on again in a split second.
Continuity mistake: In the beginning when Costello is saying: "You could become cops or criminals", he has a cigarette in his mouth, but when he leans into to say: "whats the difference?", it disappears.
Continuity mistake: In the scene after Queenan dies, when Sullivan picks up his phone, the number Sullivan calls Costigan in isn't the same as the one from which Costigan calls back, even though it's the same mobile (silver and blue vs. Costigan's red phone for Costello's gang). When Sullivan calls, the number begins with something like "617-854" and when he sees Costigan calling back, it's "617-177".
Audio problem: When Colin answers Costello's phone, we hear the girl ask, "Where the hell are you?" but her mouth actually asks, "Where the f*** are you?"
Continuity mistake: When Frank and Francis executes the couple on the beach, the woman falls almost on top of the man's back. When it cuts her body has almost moved off him. Then in the next shot she is on top of the man again. (00:04:15)
Continuity mistake: While Queenan is talking to Costello out on the street, watch the people behind him. First there's no one, then we have a shot of a woman and a huge line of kids passing next to her. Then back to Costello and the woman, who hasn't moved, is now miraculously visible behind him. To add to the mess, the kids have vanished.
Answer: It is called "Shipping Up to Boston" by the band The Dropkick Murphys, from their "Warrior's Code" album.
Vin15Nets