Lack of good storyline.

It's fun, it's light, [but] it has a hard time when its tries to get heavy.

All of these films share one commonality, that being a kind of emotional center that humanizes a cast of monsters.

There are moments in this movie where the great movie it could've been peek out... They're fleeting, here, but they're worth savoring, and they happen often enough to make it worth your while.