I ask this question the other day but the answers weren't what I was looking for... I will give some more info... I remember the lady in it was someone like Michelle pfieffer... nicolekidman... someone like that about the mid 90'sera and the man that played the husband could have been Michael douglas.. kevin costner... not to sure.. all I can remember about the movie was that They were driving I believe at night hit a body and then tried to cover the accident up somehow and I remember they were in a big house maybe on a mountain side looking into the ocean...

Are you thinking of What Lies Beneath? Harrison Ford and Michelle Pfieffer. It came out around 2000. This is what I remember from that... They live in a big house on a lake... She had been involved in a car accident and keeps seeing a woman in the water... He is a college professor... He thinks she is crazy... I think in the end he has something to do with the death of the woman and making her think she is crazy.