Continuity mistake: When Lasky heads toward the conning tower, an A-7 Corsair is shown at left (and the helicopter nose has a number "3" on it). As he is led inside the tower, the camera pans up, and now the Corsair is gone, replaced by an E-2 Hawkeye (and the number "3" on the heli is gone, too). (00:06:45)
Revealing mistake: When Richard first wakes up after travelling through time, he's supposed to be lying on a couch. Yet there is a wall behind him. It's blatantly obvious that it's the same shot from the modern bedroom, and all they did was change the lighting. (00:33:45)
Continuity mistake: There is a scene in which it is raining quite heavily and Em and Richard are inside the hutch. Richard is playing Pop Goes The Weasel over and over which annoys Em. She stabs him in the foot and he chases her outside. In this scene she is wearing a strapless dress but when he catches her and pins her down on the sand she is wearing a lacey jacket (she didn't have time to change) and there are no clouds or rain. The sand doesn't seem to be very wet either, despite the fact that it was raining heavily a few minutes ago. (00:41:10)