Factual error: The aliens request a meeting with Dr. Marvin on the shores of the Chesapeake Bay, near Washington DC. However, the shot of him driving along the shore line shows mountains in the background, which don't exist in Eastern Maryland.

Visible crew/equipment: At "Operation Sky Hook" Dr. Marvin listens back to the tape recording that he was making as the UFO flew over their car and if you look closely the spool of tape on the recorder is at the halfway spot. Earlier as he was making the recording the spool of tape was at the end. Submitted by ????

Visible crew/equipment: As Dr. Marvin tries on the alien helmet, he looks around the room and a non-acting crewmember appears in the back of the room, standing to the far right against a concrete pillar, observing the filming. Submitted by ????

Continuity: Before Dr. Marvin removes the helmet from the dead alien, Maj. Huglin is holding his rifle in his right hand. In the next shot he's using his right hand to remove the helmet. Then in the shot after that he's not touching the helmet at all. Submitted by ????

Visible crew/equipment: At "Operation Sky Hook" Dr. Marvin says to Carol, "I want you to transcribe these notes for my report" and you can see the shadow of the camera as it follows them on the left of the screen. Submitted by ????

Visible crew/equipment: Dr. Marvin decides to try out his new improved magnetic interference unit on a real alien spaceship that shows up outside the Belmont lab. As the truck with the device on it pulls up you can see the reflection of the crew in its door. Submitted by ????

Continuity: In the scene in which Hugh Marlowe and his fiancée are on the alien ship, speaking with the aliens, his arm is over her shoulder when shown from the front, but down and he is about a foot away from her when shown from behind. The shots alternate back and forth, front and behind, so that the mistake is fairly obvious.

Continuity: At Carol's barbecue a soldier drives up in a jeep with a message for Dr. Marvin stating that they lost contact with rocket No. 11. Dr. Marvin holds the message and an envelope in his hand as they look up and see the rocket burning up in the atmosphere. He never puts the message back into the envelope but when he sits down the envelope is alone and the messages is gone. Submitted by ????

Visible crew/equipment: In the final battle we can see the wires holding up the alien spaceships in the close-ups. Submitted by ????

Continuity: When they remove the helmet from the dead alien the front of Dr. Marvin's hair is combed differently than it was earlier in the scene. Carol's hair changes also throughout this scene. Submitted by ????

Continuity: As they sit enjoying Carol's barbecue the umbrella on the table behind them is tilted in a different direction between shots as a soldier drives up in a jeep with a message for Dr. Marvin. Submitted by ????

Deliberate "mistake": Two trucks with magnetic interference units on them are shot at by the aliens and the exact same sequence is used again three shots later as they shoot at them again. Submitted by ????

Visible crew/equipment: In the final battle an alien spaceship rips apart the Washington Monument and if you look closely you can see cracks in the spot where it eventually breaks apart before we see it happen. Submitted by ????

Continuity: As Dr. Marvin tries on the alien helmet the microphone on the table that Carol spoke into when they demonstrated the alien translating device is standing straight up. In the next shot it's moved sideways. Submitted by ????

Visible crew/equipment: As the saucer lands on the White House lawn a truck with the magnetic interference unit on it pulls up and you can see the reflection of the crew in the shiny driver's side door. Submitted by ????

Visible crew/equipment: The general gets a phone call just as Carol gets ready to leave his office at the Pentagon and he tells her, "You better get down to the shelter". As he says this the camera zooms in and it's shadow can be seen on his desk. Submitted by ????

Continuity: One of the three trucks used in the movie with the magnetic interference units on them has a distinctive kink in it's dish, and we see this truck destroyed by the aliens. Several shots later when the battle is over this truck is back again. Submitted by ????

Deliberate "mistake": The aliens fire on a bell tower with a clock on it. In the next shot a different building blows up. Submitted by ????

Visible crew/equipment: A soldier on the truck with a magnetic interference unit on it says, "Dr. Marvin, Dr. Marvin, we've made contact with GHQ". The crew can be seen filming across the street in the reflection in the truck. Submitted by ????

Continuity: A saucer crashes threw the main window of a train station and the clock reads 11:10. Two shots later we see the clock on the other side of the building and it reads 10:43. Submitted by ????