My wife watches all the Law and Orders, Without a Trace, Medium, CSI, etc ... all those TV crime dramas. They get very predictable. As soon as one guy looks very much like the culprit early on, you know it's not him. It's always the guy who enters about a quarter of the way into the show, says something a little odd, makes a face, and exits kind of awkwardly. That's the murderer, haha.
Either that or some crazy twist with 10 minutes left in the show.