Looking for the name of a movie! Please help

I remember watching a horror movie along time ago and the only thing that I really remember about it is that at the end there were these monsters and this guy was in a helicopter and he picked up a woman who was being attacked by these creatures. When she is finally safe aboard the chopper they smile and then find out that one of the things is on the chopper and the movie ends. If you or anyone you know has any information please contact me. Thanks