Forget the 3D aspect of the movie, as it was an afterthought (like it seems to be with most 3D movies these days), and it ended up being nothing more than a marketing gimmick. It did nothing to enhance the movie or make it more fun. At all.
So forget about that mess, and let's concentrate on the plot.
On the way to the hospital (why?), the Cop and Paramedic talk about souls or something, only to have Abel sit up and slash the paramedics throat with a hidden knife. Yeah. The ambulance flips over due to the knife violence, and Abel escapes into the river, as do all of our hopes for this movie... and that's just the opening sequence.
|"What is this shit?"|
|The knife is family.|
|My, what big hands you have... for a small Teenager.|
Whatever the reason, we're the ones suffering for it.
|Yeah, we want vengeance too.|
Just skip it and know you're better off for doing so.