Shadowland

When Detective Ian Gates wakes up in the hospital he has a head wound and no memory of what's happened to him. Despite that he wakes up a hero, the admiration of a terrified city raining down on him for apparently ending the lives of a pair of dangerous killers in the process of saving a young woman's life.

However, as the haze clears, bits and pieces of the night he landed in the hospital beginning to return, two things become frighteningly clear. He may not have been as much the rescuer as the one being rescued. And, whoever or whatever he was being rescued from... was not human.