A few years back, a colleague of mine told me it was a very interesting documentary and he lent it to me. First of all, I want to give some credit to Leonardo DiCaprio for trying to bring us some awareness about this subject. The main issue I had is that, even though the subject was really interesting, the movie was actually rather boring to watch. In my opinion, a documentary must be interesting and must provide some useful information but it also has to be entertaining somehow. I above all blame the directing and editing for this. Indeed, the whole movie is just a succession of scientists talking and then between those (sometime tedious) interviews, you had some short film showing the decaying nature (also rather tedious...). Later on, I have seen 'An inconvenient truth' which basically deals with the subject and it worked better above all because it was much more compelling to watch. To conclude, even though it is rather underwhelming, I still think it is an interesting documentary and it is definitely worth a look, especially if you are interested by this subject.