Corrected entry: In the scene where Bruce Willis puts the real Nick Fisher's body into a truck he rolls it up a ramp into the truck. Later when the truck is seen driving along the highway there is a lift gate on the back of the truck which means it would not have a ramp.
Corrected entry: Jesse Gonder was long gone from the Mets in 1979. He last played for them in 1965.
Correction: This is likely a valid mistake, but needs more information as to how it pertains to the movie.
Corrected entry: Throughout the movie we are presented with several different views of what the mansion looks like. At the beginning when Loomis plays it, later when the group does, and at the end when they finally enter the mansion, we are given 3 totally different mansions.
Corrected entry: When the Boss's men come to get Slevin, he already has some marks on his face from being punched in the nose. But when he is in the car with the Boss's men (after one of them had broken his nose again), the marks on either side of his nose have gone, but are back when he meets the Boss.
Correction: Those are dimples in the bridge of his nose; if you notice Josh Hartnett has a bulge there. When he moves around you can see the dimples change color or disappear.
Corrected entry: In both scenes where Bruce Willis comes down the elevator thing in the car garage (in the regular storyline, and the retelling later), he shoots one of the bookies in the back. The camera angle shows the shooting happening with the car in view. It is plain to the eye that the driver's side window looks already shattered both times.
Correction: It only looks like it's broken, but it's actually wet from rain or morning condensation.
Corrected entry: When Lindsey takes a photo of 'Smith' she moves in front of him to take the picture, yet when she shows Slevin the picture, the picture is of a side profile not face on when she took it.
Correction: That's because she took it on a camera phone, on some phones the pictures aren't taken as soon as you push the button, so she may have pushed it when she was in front of him, but then as she moved back it caught the image.
Corrected entry: As Slevin is walking down the hallway to The Fairy's apartment, his hair changes between shots. It goes from sticking up to slicked down to sticking up and back to slicked down again.
Correction: His hair changes because they keep going back on shots. When it is sticking up, he is walking to the Bosses place, and when it's down, he's walking to the Fairy's place.
Correction: Lift gate rental trucks have both a ramp and a liftgate on them. Budget Truck Dealer - 7 years.