I’m an aquatic plant scientist, and this documentary is impeccable. I’m currently finishing a book on my research on hydrophytes over the past couple of years, and I can’t stress enough how impressed I am with the Water Worlds episode. I’ve worked in some of the filming locations, and this is one rare case where the film does do justice to the location. I’m jealous that the writers were able to describe adaptations so simply in a few sentences, whereas my research of the same organisms is written in long boring paragraphs. This is my favorite documentary I’ve ever seen, and I highly recommend.