Actually, the title of this post is a little misleading. A Mighty Heart was more like Karachi Vice, as halfway through the movie and for a good 40 minutes, it was like Michael Mann took over. Everything was at night, there were random camera angles (below the actor, above the actor, in front of the actor, up the actor's nose), and there were an awful lot of cops. And God forbid if you blink, because you'll have no idea what's going on.
In truth, the movie was actually half-decent, but could have been a lot better. For one, it was based on a book that was very clumsily turned into a screenplay. In the book, I'm sure there was time to develop antagonists and protagonists. In the movie, you never really feel for the main characters because you barely meet Daniel Pearl - the kidnapped - and never develop a dislike for any of the numerous enemies because they're found out, grabbed, and give up the next guy all in about three minutes each.
There is also very little dissection of the possible motives behind the kidnapping. I realize, having followed these events, that they were mostly in the dark, but it's very difficult to tell whether they thought it was because he was American. Or Jewish. Or a journalist - the rights stripped from whom and the killings of whom were, sadly, barely mentioned in the movie. Or hell, just because he was in the wrong place at the wrong time
As for Angelina Jolie, she actually was pretty good. It's definitely not an Oscar-worthy role because she simply doesn't get enough meaningful screentime (and the time she was on-screen were borderline worthy). Although she did manage to dissolve into the role - believe me, when I first saw the trailers, I didn't know who she was - such a big star was an odd choice for such a scattered role. Emotionally, she doesn't quite seem to have a handle on what the situation calls for, but she performed very believably, albeit long-windedly at times - her reaction to news of Danny's (actual) death rivals Hayden Christensen's "Noooooooo!" in Star Wars: Episode III.
Beyond that, there wasn't really much to glean from the movie. Names and organizations are tossed about, but they hold no real weight - there is mention of a connection to al-Qaeda and the attacks on the World Trade Center, and then they are never mentioned again.
Characters are introduced and then vanish - an FBI agent enters and abruptly has the entire room cleared of about 20 people because she has a highly confidential phone call. This is about 25 minutes into the movie. It is also her only scene. Literally, she's not even in the background afterwards, and you never find out what the call was.
There were pluses, though, I swear. It was a story that needed to be told. The acting all around was top-notch. They stayed very true to the story. Overall, though, for this story to be turned into a movie, it should have been drawn from another source, with all due respect to Ms. Pearl. Some books should remain just books - maybe that's why hers took so long to be turned into a movie.