The Italian in the ship's log is incorrect when Epps looks up Katie's entry. She is listed as "viaggendo solo". The word "viaggendo" is incorrect, and should be "viaggiando". Since Katie is female, the adjective "solo" should also agree and be "sola", so the entry should read "viaggiando sola".
In the first scene, Francesca sings "Senza Fine" through once and then begins to sing it over again. When she sings "Cio che abbiamo gia vissuto senza fine" her next line should be "Tu sei un attimo senza fine," but instead she sings "Tu per me sei..." before the song is cut off. The first of several lines that begin with those words comes several lines later in the song.
Throughout the film, the doors to all the cabins are seen to open to the inside. Yet, when Epps is wandering the ship looking for Katie's cabin, all the doors in the hall automatically slam shut in a row and close from the outside. When Epps sees Katie's cabin door open, it opens to the inside.
When Epps is talking to Munder and Dodge next to the two water pumps draining the engine room, both the hard suction line and the flexible discharge line are in the water. The discharge line was previously thrown overboard by Epps and shouldn't be in the water.
When the Arctic Warrior first collides with the Antonia Graza, it strikes just above her name on the bow. In the next shot, the Warrior is seen bouncing off the hull just aft of the bridge, and a final shot shows the Warrior backing away from the Graza near the stern.
When Jack and Epps find the crate of gold, it is open and full of rats. Later, Greer has to prise off a padlock with a crowbar to reveal the gold in the crate, and no one mentions the already open crate.
The ship is supposedly caught up in a rotating current in the Bering Sea. North of the equator, this would be moving the ship in a counterclockwise direction, driving its right (starboard) side into the rocky islands at the edge of the current. As shown, the ship's left (port) side is at risk, meaning that the ship is drifting in a clockwise rotation. This would be the norm south of the equator, where the movie was filmed.
In the sequence immediately prior to the Arctic Warrior finding and striking the Antonia Graza, at least one small ship or other structure is barely, but distinctly, visible on at least two occasions in the sea in the gloomy background. If this is the middle of open sea, they shouldn't be there.
The two-way radios used in various scenes show all of the crew communicating, even though the antennas shown on the radios are using different bands. Some radios have an antenna used with the 400mhz band and others with the 800mhz band. The 800mhz band is almost exclusively used with repeaters and require the radio to be within a few miles of a tower. Although 800mhz radios can be used "radio to radio" they are very expensive and would be useless on the open seas.
Murphy states that, in the sixties, the Italians could not compete in speed, so they built their ships to be extremely big and luxurious. That is factually wrong for two reasons: first, since the 1940's, Italian ocean liners were known, precisely, by their speed (the most famous of them, the SS Rex, held the Blue Ribbon award for four years). Second, Italian liners built immediately after WW2 were indeed very luxurious, but not very big. The SS Andrea Doria (after which the film's Antonia Graza is modeled after) was barely 200 m long, a full 100 m shorter than the largest ship of its time, the RMS Quen Elizabeth.
While exploring the liner, Captain Murphy finds a blood stained straight razor in the captain's cabin. Dry blood is brown, not dark red. A blood stain that color it should be hours old, not decades, and when Murphy finds it he could have been easily dismissed it as just rusted.
When the Arctic Warrior finds the Antonia Graza it is night time. The Arctic Warrior would not be running with the lights on inside the pilothouse because it makes it hard to see out the windows due to glares from the lighting inside the boat.
In the shockingly gruesome beginning, after the cable wire whips through the crowd and cuts the passengers in two, some passengers are shown alive and moving after they've collapsed to the floor. This is not accurate, as people who have their upper and lower halves separated will go into massive shock and die quickly thereafter.
When Epps breaks a cabin window and throws the pump discharge line out the window, we see in the shot from outside the ship that the water is being discharged from at least five decks above the water-line. The engine room was below the water line, and no one would run a hose up an extra five flights of stairs when they could run it overboard just above the water-line, unless the cabins on the other decks were locked by their former residents/ had rusted through floors/ were otherwise unaccessible. Continuing up another deck would be preferable to wandering the decks on the chance of finding an open cabin, as people generally lock the doors to their rooms when they are not in them.
When the salvage crew first arrives on the Graza's bridge, Dodge makes a comment that she "must have run on full throttle 'til she was bone dry." Earlier in the film, after the massacre on the bow and Katie's screams, there is a shot of the Graza sitting dead in the water. However, it is possible that the soul-gatherer piloted the ship around the world looking for souls and then ran out of fuel.
The Antonia Graza is owned by the Italian line. However when the salvager's find the ship it is in the Bering sea, which is by Alaska. The Italian line never ran ship anywhere near there. And Katie says that she was going to New York, which is on the complete other side of North America and Katie has an English accent. So the ship should have been on a transatlantic voyage but it was found adrift in the Bering sea, though it is possible that the soul-gatherer piloted the ship around the world looking for souls before damaging the ship and forcing a stop.
Except for Katie and the recent crew members bodies being found, there is no explanation for how the remains of the murdered passengers, staff, and crew disappear and/or go unnoticed. Considering everyone except Ferriman was killed, there was no one to move the bodies. Especially from the pool.
When the Arctic Warrior is searching for the Antonia Graza it is shown traveling through a bad storm. There are many shots of the outside of the boat with driving rain and lightning however the sea remains flat calm the whole time.
After the team decides to take the gold and leave the ship, one of them slaps the lid closed on one of the cases of gold which makes it move a lot. With the amount of gold in it that was shown, it would be too heavy to move simply by slamming the lid closed.
Though the Antonia Graza is supposed to be an Italian ship, there are several glaring grammatical errors whenever Italian words are visible on screen. The most evident of these is the plaque sporting the phrase "Cabina di capitano" (outside the ship's captain cabin) instead of the correct "Cabina del capitano". Other visible errors include gibberish on a can of rat poison in the galley.
Though Francesca (the lounge singer) speaks perfect Italian during the rest of the movie, the song she performs during the title sequence ("Senza Fine") is sung in heavily-accented Italian. (Italian actress Francesca Rettondini is lip-syncing a non-Italian performer.)
When Epps is sent to repair the sinking oil rig at the beginning of the movie, both Dodge and Munder are on the Artic Warrior. Epps slides across the cable between the ships then drops down into the oil rig. Immediately after she does this, we see both Dodge and Munder on the oil rig looking down at Epps.
When the crew blow open the door to the room with the gold, the door is blown from the inside out. If they were able to get in to plant explosives, why did they need them? Also, a blast of that size would have set the mail bags on fire.
In the opening scene when the wire slices through the attendees of the Captain's Ball, everyone but the captain is cut in half. There was no way that the wire could cut the captain's head exclusively, and not cut Katie in half.
Before Francesca's death, she shoots the man in the white
jacket. Then after she meets her gruesome fate (once you get an aerial view of the hook) you can see the man with the white jacket lying dead next to the car. But when starts swinging back and forth, the man's body disappears. When you get to see another aerial view of her spinning around, the body is there again.
The movie takes place in the Bering Sea. Epps is floating in the sea prior to her rescue, yet shows no sign of the water being cold. Even on the warmest summer day, she would likely die from hypothermia in these waters. An average person, wearing light clothing and a personal flotation device (PFD), may survive 2 1/2 to 3 hours in 50° F water.
Just after the Arctic Warrior explodes, Epps jumps from the Antonia Graza's forward well deck into the water and emerges unharmed. The well deck is at least 6 or 7 decks above the waterline, and such a fall would have caused a great deal of pain and possibly some broken bones.
Near the end of the film, Epps tells Dodge to take the helm to steer the drifting ship away from the rocks. The rudder of a drifting vessel has absolutely no effect on the direction of travel; a vessel must be "making way" through the water for its rudder to work. The vessel also has no power, and the engine room is flooded. The steering gear room would be underwater. So the helm controls would be dead.