Derailed (2005)

Clive Owen's in a happy -- though maybe a little stale -- marriage. He winds up flirting a bit with a fellow commuter (Jennifer Aniston) and can't leave well enough alone. So he checks her company's website and gives her a call...then they grab a bite and enjoy each other's company...then they decide to enjoy each other even more.

The fun ends before it can really start when their hotel room is invaded, Owen is knocked down, and Aniston is assaulted right in front of him. Saying much more could spoil the script's "surprise" -- but, basically, his life becomes a nightmare. An eye-rolling nightmare, but still.

Between this and Fatal Attraction, I don't know why men ever cheat.

C-