Dr. Brady Barr wants to make history. Out of 23 crocodile species, he's captured all but 3. And these are not your average crocodiles; they are some of the rarest and most endangered animals on the planet. So it's going to mean traveling to far-flung locales and traveling for days on foot. He only has once chance, one opportunity to capture each of these species - and that's if everything goes according to plan. This may be Dr. Barr's toughest assignment yet.