The helicopters at the landing site escort the saucer down, then immediately disappear. They are completely gone as the saucer touches down and do not participate in the ensuing battle, even though the Martians are never seen aiming their guns in the air. See more...
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Mars Attacks! (1996) - 2 with pictures
Screenshots of mistakes that have been online for less than a year are only visible to members, but the rest are available to everyone. Don't forget to check out the picture of the day, updated daily, and the top 30 screenshots too.
Continuity: When the press secretary kisses the hand of the alien-dressed-as-a-seductive-woman, the eyeball ring is on her right middle finger but after she knocks him out (or kills him) the ring is on the finger between the middle and the pinkie. In subsequent scenes it's back on the middle finger.