Continuity mistake: When Harrison Ford is watching his wife laying in the bathtub ready to drown, the camera shoots her head several times between cutaways to Ford and the running water. Watch her head relative to the top of the tub in the various shots. In some her head is much higher than in others yet her body never moves.
Continuity mistake: When Claire is in the tub after her husband gives her a drug to immobilise her, watch her hair in various shots. It keeps changing position even though she is unable to move it out of the way with her hand.
Trivia: There are more than a few Hitchcock references in this movie. Most notably Harrison Ford's character - Norman (Psycho), suspecting the neighbour of murdering his wife (Rear Window), Michelle Pfeiffer falling in the shower and pulling the shower curtain down with her (Psycho). There are many others if you watch for them.
Question: When Norman says the guy "that wrote that book he loves" (Shumway?) congratulated him on Spencer's Theorem, then Claire says "He didn't know your father was dead?" and Norman says "He knew". What does one thing have to do with the other? I've seen this movie at least 20 times and I can't figure out this conversation.Ingabritzen