Okay, so, we've met William Bell, we know its an alternet universe. But...I'm confused, and not in a good way. What now? I mean...haven't we figured everything out now? Am I correct that Bell (ie. Massive Dynamic) was the one who did those attacks? Or did Nina say that he/it wasn't? If he was, what happens from here?

I love this show and have the most faith in the world in J.J. but it feels like the plot kind of died. Can someone refresh my memory...there are more mysteries in this show right? And more to arise?