Continuity mistake: When the three T-Birds go to moon at the TV camera at the National Dance Off, Doody says "1, 2, 3, go!" and pulls down his trousers to his ankles. In the next scene, his trousers are suddenly pulled right up to his buttocks.
Continuity mistake: In the scene in the Beatles hotel room where Nancy Allen comes out from under the cart with the cokes on it, when she first sees the Beatles' guitars, notice that in the very first scene, the Hofner bass is left handed (the pick guard is on the left as you're looking at it), then it cuts to her, then when it cuts back to her rolling on the floor with the bass, it's suddenly right handed, then when in the last scene with her handling it, it's left handed again.
Continuity mistake: During the classroom scene, Donald Sutherland writes the word "Satan" on the board. In the first shot, the "t" in Satan in directly over the crease on the chalkboard. In the next shot, it is clearly on one side of the crease. (00:18:00)
Continuity mistake: Kal-El's cradle arrives on earth, flies zooming past the Kents' car, which is driving in the opposite direction and crashes 500 meters behind the vehicle. The car keeps moving for about 200 meters and then pulls over. A brief shot shows an intact curb on the right. However, when Jonathan Kent gets out of the car, everything changes: The cradle has moved 700 meters ahead and lies next to the car; and the immaculate field is now destroyed by a huge ditch.
Continuity mistake: As Max is carrying a birthday cake out of the kitchen, the candle blows out as he walks. But the candle is suddenly lit again when the camera angle changes, as he walks into the living room.
Continuity mistake: When we first see Hannah, her room number at the Beverly Hills Hotel is 305. Later, when she and Bill return from a day at the beach, the room number is 306.
Continuity mistake: When the taxi driver sets off in pursuit of the white truck, only the driver is seen at the wheel and Robert Mitchum is not sitting in the back. In the next shot of the taxi, Robert is seen in the back of the taxi.
Continuity mistake: Marsha Mason is standing between Abe Vigoda and Vic Tayback.After a quick close-up of Peter Falk suddenly she is standing next to Peter.
Continuity mistake: Near the end of the film, when Richard Gere and Brooke Adams is by a boat and attempt to escape up the river, Gere is shown waving a kerosene "barn lantern" to illuminate the boat. In a slightly later shot, he is doing the same thing, but the lantern has become a Coleman gasoline lantern. These lanterns had not been invented yet in 1917, the year during which the scene in question takes place.
Continuity mistake: In every case, the pod needs hours to take over the human, but, in Elizabeth's case, she gets changed in less than 5 minutes. (01:24:00)
Continuity mistake: When Emmannuelle first speaks to the butler at the front door, the door is ajar from the front, but completely open from behind. (00:07:30)