First, there seems nothing wrong with this movie. Not the visuals, not the acting. There might be a few inconsistencies that bother the hard core physicist, but that does not matter. In fact there is no single detail there I would really object to emphatically.

But there is one thing seriously missing - a story. The heroine falls from one hole into the next until the very end. That's it. It's a roller coaster ride not more and while that's entertaining at times, it is very very empty. It should be played on a Disneyland ride or used in cut scenes for a video game, but it does not hold as a movie.

Being void of dialogue and relationships makes this movie very boring and meaningless. It is hard to empathise with the main character at all. And this is no fault of Sandra Bullock, but of the screen writing, or the lack of it.