Blooper

When the deaf girl enters the elevator, there is nearly 8 minutes on the timer until the engine room shutdown. Then, nearly 2 minutes after the explosion, the elevator stops. The likelihood that anyone would be in an elevator on a ship this size for 10 consecutive minutes is unrealistic.

After appearing barefoot and taking off his white shirt, Alex appears in the next scene wearing a black shirt and black sneakers.

Before the collision with the Eindhoven Lion, The Seabourn Legend sails towards the Coast, but right after the collision with The Eindhoven Lion, The Seabourn Legend turns 90 degrees and it's facing towards open sea. But later, the ship is still sailing towards the coast.

The starboard bow thruster is used to turn the ship. That would turn it to port, whereas it turns to starboard.

The leaches bite marks appear and disappear seconds later on our terrorist's first night onboard.

In several scenes, many passengers are stuck behind "fire screen doors" and unable to get out. These doors open like any normal doors with the recessed handle built right into them. You can see this handle when the chainsaw is used. Even if the passengers were somehow stuck behind water-tight doors, those can always be opened via a manual crank.

No ship has ever been - or ever will be built without having emergency fuel shutoff devices that can be manually operated.

Supertankers the size of the Eindhoven Lion carry crude oil. Crude oil does not explode like refined gasoline would.

The ship's propellers are shown rotating far too quickly. On a ship that size, they might rotate as much as 1-2 revolutions per second at full speed.

When the Seaborn Legend is plowing down the ships in the harbor, its anchor strikes a small sail boat in the side, this wouldn't cause the sail boat to blow up like it did.

When the captain first sees Geiger in uniform, he assumes Geiger is the chief engineer. However, he would immediately notice that Geiger's epaulettes have four stripes (captain rank), and would know something was wrong.

On the engine room door, a sign is in English and Norwegian or Danish. Which is strange for a cruise on the other side of the planet.

Fire doors aboard modern liners are made of maritime steel, a hardened metal sometimes 2 inches thick and covered with flame retardant paint. There is no way a regular chainsaw could cut through them, much less as easily as shown in the movie.

When Alex is in the water, after the winch snaps off and he is climbing back onto the access door, the ocean is not moving, even though they are supposed to be traveling at 17 knots.

Just before first mate Juliano is injured by the flying cable winch, it is possible to see the theatrical blood already applied to his arm

A ship's hull is made of steel, not aluminum as shown when the tanker's anchor rips through the ship.

At the end of the movie when Sandra was tied both hands and in the jet boat, she pushed a lever to separate her jet boat from the villain, at the point of separation, you can see both of her hands were on the handlebar, untied, then in a few seconds later, her hands were tied up once again.

When Gieger repeatedly swings the lamp towards the captain, the captain continues to move along the wall towards him. Once Gieger's threatening intentions were made clear to the captain, it would have made more sense for him to back AWAY from Gieger when given the opportunity.

There is no reason for a chainsaw to be aboard a boat. Especially a cruise ship. The chainsaw's sole purpose is to cut wood, specifically trees. Also, the exhaust fumes from running a gas powered chainsaw indoors would be hazardous to all involved.

When the screen is showing the propeller status, you see the port propeller on the screen going the opposite direction to the starboard and the actual propeller.

About 2 seconds after Geiger pushes the captain off the ship, 2 females walk over to Geiger and ask to get a picture taken with him. They would have easily been able to hear the captain's screams being that close at that moment.

When Alex is clay pigeon shooting, this would not be possible due the fact that the ship is still moving so the distance to shoot them would be greater than if was still. Also, unless their room as close by, the sound of the shots wouldn't of woken Annie up.

The shotgun used is a semi automatic and not a pump shotgun. Still you can hear a pump revelation 5-6 times.

Reflected in Tuneman's sunglasses during the speed boat/airplane chase.

Reflected in the glass in the mall.

When Alex tries to rescue Drew from the ballast room flood, but they are caught and the water starts to engulf them, he says to her "Hold onto me." Drew is deaf (which Alex knows).