This is from a review I posted on OWW. I thought this was worth keeping.

Have you seen The Life od David Gale? If not, get it, it's worth seeing. Anyway, I'll try not to spoil anything. In the opening scene you see a woman in a car that breaks down and stops, and she leaves it in the middle of the road and runs like a maniac, a videotape in her hand. You don't know who she is, or what this is all about--and you won't till the very end of the story. But when the movie proper starts and the woman proves to be a journalist interviewing a guy on death row scheduled for execution, you know that she will discover something--probably that he's innocent--you know that she will be the only one able to prove it, and that she will try very hard to do that. You don't know anything more--not if she will manage, not what the story really is about. But the fact that you know that something along those lines will happen keeps you at the edge of your seat even before the story starts. AND without really giving away anything. Brilliant.

Note to self:

Foreshadowing is key. Give things away--something that comes at the reader out of nowhere is not really a surprise--it's a lost opportunity to build tension in the story. Not knowing doen't really produce the "edge-of-your-seat" fiction. It's the expecting-but-not-knowing-and-fearing thing that does.