A depressed woman learns that her husband was killed in a car accident the previous day, then awakens the next morning to find him alive and well at home; then awakens the day after that to find that he's dead.
 
You will constantly be piecing the puzzle together instead of enjoying the film.  
 
FUN FACT:  When Sandra Bullock was restrained and struggling in the hospital scene she really did cut herself by accident. So instead of using a body double for the injection, it really was Bullock who got the Tetanus shot in the scene.