This General is the senior military official who advises the President on possible military options in the face of the alien menace in the sky. He suggests evacuating the President early on, but the President waits in an attempt to calm the American people. The General is also quick to suggest a fighter jet attack and ultimately a nuclear attack. These initial means fail and casualty figures worldwide are staggering.

David Levinson is a computer programmer type that uncovers a message being sent from the alien ships circling the planet. He interpretes it to be a countdown; a countdown to an attack on the world. With motivation from his father he drives to the Whitehouse to explain his thoughts on the aliens to the President. Because of his theory of a countdown, the Whitehouse is evacuated just before it is destroyed. In a secret Area 51 complex David is shown alien technology from the fabled Roswell crash in the past. From this technology he is able to create a computer virus that could take down the forceshields of the Alien vessels circling the globe. Thanks to David's virus invented on a an Apple Macintosh computer, the alien's shields go down on their ships and humanity is able to deliver a decisive blow against their would be unearthly exterminators.

Russel Casse is a somewhat crazy character in the film. When the aliens attack the world he takes to the road as part of a motorcade of driving campers all seeking refuge in deserted areas of the world. After alien attacks take out most of the trained pilots of America, Russell enlists as a volunteer to pilot a jet fighter against the alien spaceships up above in the sky. Russel dies sacrificing his life to take out a giant alien spaceship when he runs out of missiles.

These two are the wife and child of Airforce pilot Captain Hiller. When Los Angeles is virtually destroyed, Captain Hiller assumes his wife and daughter are both dead. But Jasmine Hiller manages to take refuge from the attacks and survives to travel along with the the First lady to take refuge in a military command post.

This character is the keeper of Area 51 and the head scientist there. In his posession is a crashed alien spacecraft from the legendary Roswell, New Mexico crash in 1947. With a little reengineering this craft is made functional and is used to deliver a computer virus into the heart of the alien command structure technologies.

This is the Secretary of Defense. In reality he would not know things that the President does not know security wise. But in this film, this Secretary of Defense knows of a secret research complex; Area 51 that neither the President nor his top general are aware of.