Warning: This post contains major, movie-ruining spoilers for My Bloody Valentine 3D and The Uninvited. Don't read it if you haven't seen them, or if you have any intention of ever seeing them.

January leftovers My Bloody Valentine and The Uninvited have a few superficial things in common. They're both remakes (of a 1981 Canadian slasher film and a 2003 Korean thriller, respectively), they're both set in rustic little towns, they're both meant to scare you. But as those of us who have seen both films know, they also share a pretty significant plot device. We'll talk about it in the next paragraph, after one last spoiler warning.

Both films end with the surprise revelation that the protagonists, both recently released mental patients, are the real villains, and that they're so crazy they don't even realize what they've been doing. This is convenient, because it means the audience -- seeing the story through the protagonists' eyes -- has been in the dark, too. In My Bloody Valentine, the masked killer turns out to be Tom (Jensen Ackles), who has spent most of the film trying to stop the masked killer, unaware that it was himself. In The Uninvited, Anna (Emily Browning) has been convinced that her dad's girlfriend is trying to kill her. But as it turns out, Anna has been imagining it all, including conversations with her sister, Alex (Arielle Kebbel), who actually died a year ago. When "Alex" kills Dad's girlfriend at the end, it's really Anna holding the knife.

Neither of these films is the first to use the old split-personality-murderer trick, and the fact that they've been released two weeks apart is just a coincidence. But what does it say about modern scary-movie making?