When Michael jumps from the derailing car he lands on the front of the last car, but when he's pulled back inside, he's in the door at the back of the car instead of the front.
During a fight scene a little over an hour into the movie, Liam is using a guitar that changes colors from black to red (or a dark wood grain).
Towards the end of the film, once the train has stopped the external shots clearly show there are lights on inside the train, however the inside shots are in the dark with minimal light.
After Neeson is hit on his face a little boy is pointing to his nose because it's bleeding. He takes a tissue and that one is all ready red before cleaning his noise/face.
After coming out of the portal but before 125th Street, they cross the same bridge twice (which is on the NYC subway 6 line and does not even share the same tracks as Metro North).
NYPD has no authority to leave the city limits and take charge of any crime scene let alone a hostage situation in another county. The Westchester County Police and Metro North Police would handle the stand off.
There is nothing remotely like the scope the police snipers have at the end of the film. Nothing (but complex, close-range, multi-antenna, experimental systems in university labs) can see through walls, and nothing can see through metal walls.
When the assault team are at the entrance of the train and were told to back off, the point man repeated this message to his men. An assault team in this covert style would not use voice procedure, it would be complete hand signalling so as not to let the hostage taker know an assault is imminent.
The NYPD does not patrol inside Grand Central Station. The Metro North Police are responsible for the station and all the rail lines.
The train Neeson's character rides is the Hudson Line of Metro-North, yet the station stops depicted as he returns home from Grand Central Terminal to Tarrytown are clearly NYC subway stops (86th Street, etc.). Metro-North commuter trains do not share train tracks or station stops with NYC subway lines.
When the emergency brake on a train is pulled, it does not require any action from the engineer to stop the train. The system will force the train to stop (quite quickly, in fact) and will require human intervention only to reset the system to get the train moving again.
However, it did appear that there was an explosion when the emergency brake was pulled indicating it may have been sabotaged. If the emergency brakes had indeed failed to activate, the engineer would be needed to stop the train.
However, it did appear that there was an explosion when the emergency brake was pulled indicating it may have been sabotaged. If the emergency brakes had indeed failed to activate, the engineer would be needed to stop the train.
Alex stabs and slices several people many times in the final fight scene, yet when he drops the knife there isn't a speck of blood on it.
Early in the film, Neeson is walking across the main concourse in Grand Central Terminal toward the East gates. Sunlight reflects on the floor through the windows on the east wall. No sunlight has reflected on the concourse floor since the construction next door of the old Commodore hotel in 1929. The old Commodore (now the Grand Hyatt) is actually on the South/East side of Grand Central. The windows on the East side (above the Apple Store) are unobstructed and sun does come through.
The commuter train line is shown to only go as far as beacon, with the tracks ending shortly after the station. In real life, the commuter line has two more stations, and the tracks keep going north.
In the film, Tarrytown station has two side platforms and two tracks while Beacon station has four tracks. The actual stations are opposite, Tarrytown has 4 tracks on two island platforms while Beacon station has two tracks.
When Michael is checking seat checks, he asks a passenger if the train stops at Tenmile River, to which the passenger responds "Yeah". Tenmile River station, however, is on a different line.
One of the "stations" between Grand Central Terminal and 125th Street has "HP" mosaics on the wall - - HP stands for Hunts Point Ave in the Bronx - - a NYC subway station which does not share the same tracks as Metro-North.
The station names depicted in this film have purple bands. Metro-North's Hudson line is considered to be a green line and thus uses green bands above station names.