Insurgent
I'll start by saying I didn't enjoy this half as much as the first one (and it had been a while between books, so I had to go out and buy Divergent on DVD in the quickest and easiest way of catching up).
I thought it would have been as good if not better but the main reason for me reading it (the romance) kinda took a turn for the worst for a lot of this with arguments and lying and going behind each others backs.
As for the rest of it, it didn't draw me in as much as I expected and in fact I got a little bored in places.
The best bit was the ending for me, not because it was the end but because of what came out in that video that was played.
I'm going straight onto the last book but it may take me a while to read.