Revealing: Dakota Fanning cannot actually see the computer generated birds that are flying high over the Hudson-Athens ferry. If you look closely her eyes stair straight ahead and not up in the air where they should be.

Audio problem: As Tom Cruise and the children walk towards the Athens NY ferry an older gentleman says, "We got it the worst, that's what I heard". If you look closely his lips do not match what he's saying.

Continuity: When Rachel says Ray should get TiVo, she is looking at her hand. When it cuts she is suddenly resting her head on her hand.

Other: Mary Ann and Tim's basement, and Ogilvy's cellar are the same set, just dressed differently; note the positioning of the windows, the stairs, even the little room off to the side. Also, some items in both the basement and cellar are the same, for instance the chair. While they are in the basement and the plane is crashing, before they run into the side room, Ray grabs his gun off of that chair and later in the movie when they are in Ogilvy's basement, Rachel is in that chair when the aliens are in the cellar.

Audio problem: When Tom Cruise gets back to his house after the first encounter with a machine, Robbie's says "What happened?" but nothing is heard, then he says it again and is heard the second time.

Other: When Dakota Fanning and Tom Cruise are in the house being searched by the alien probe, they use a mirror to shield themselves. We can see a diverging beam of light coming off of the probe, and therefore we should be able to see a related beam coming off of the mirror, widening even further. No second beam is visible.

Continuity: While up in the tripod’s "holding cell" for humans, Ray spits the circular grenade pins into his hand, and their positions on his palm differ between the two consecutive close-ups.

Continuity: When Ray carries the Pennzoil box of groceries into Mary Ann’s house, the goods change position between shots.

Continuity: When Ray and others are crouched beside the hole in the asphalt, the guys around him and the way he holds the freezing piece of asphalt, differ between consecutive shots.

Continuity: When Ray is at the News Producer's van, she grips and starts to push the videotape with her palm up, but in the next close-up it's the opposite, she's pushing it with her palm down.

Continuity: In the first shot as the church sustains damage, a long massive crack rips up the asphalt and concrete sidewalk under the streetlight then makes its way up the building. However, in the next shot, even as the church receives more damage, the previous damage to the asphalt and concrete is gone and there are actually people standing around that streetlight.

Continuity: As Ray says, "Next time you take my car with no driver’s license…" he walks a good distance away from Robbie. Yet in the next close-up of Robbie, Ray’s arm is still pointing up near Robbie’s face.

Continuity: In one of the earlier scenes where they are in the dad's house, just before Rachel tells Ray that Robbie took the car, Rachel is slouching on the couch with her left leg crossed over her right. In the next shot she is sitting up with her hands on her face, and now her right leg is crossed over her left.

Continuity: Ray and Rachel are about to walk down into the basement at Harlan's house, the door on the right of the bulkhead is open and the door on the left is closed. In the view from the basement you will notice that the door on the left is open and the door on the right is closed.

Factual error: As Tom Cruise and the children walk on route 385 towards Athens NY they pass a sign saying that the town is 1 1/2 miles away just before they cross a bridge. In reality there's no bridge to cross 1 1/2 miles from Athens NY on route 385.

Continuity: As the boy runs up the stairs to the second level of the ferry Tom Cruise yells, "Robbie". If look closely there's a large speaker in front of him that can be seen in the first two shots but then disappears for the rest.

Continuity: In the van, when Ray says to Manny "Get in, or you're gonna die," the next shot shows Rachel's face with tears in her eyes saying "What do you mean?" with a very distressed look. In next shot from the left side of the van, you can see Rachel on the right side of the screen with a different expression on her face, looking more calm, yet, in the next shot the look on her face is distressed with the look of crying again.

Continuity: When Ogilvy shouts Ray's name half a dozen times, Ray runs to him to quiet him down. The broken cellar window behind Ogilvy has shards of glass and red roots growing on it. Then in the next exterior shot, the shards of bloody glass are different size and shape, and the roots differ as well.

Audio problem: After Ogilvy is dead, when the alien snakelike giant eye surprises Rachel she begins screaming. As Ray hacks away at it with an axe, she stands at the wall screaming, and when the last long scream is heard, her mouth is closed just before Rachel runs to the stairs.

Continuity: When Ray places the blindfold on Rachel's eyes, while in Ogilvy's cellar, its position and folds differ in consecutive shots.