As the human population booms and climate change becomes more urgent, nature docs have almost no choice but to become increasingly tragic. The Last Lions, about a female lion and her three cubs adapting and surviving in a corner of Botswana, exists in part to raise awareness of the rapidly shrinking big cat population due to human encroachment. No humans appear onscreen, though thanks to some occasionally eye-roll-inducing narration from Jeremy Irons, we're reminded that many of these lions' challenges are outside normal circumstances. Made by a husband and wife team of explorers-in-residence at National Geographic, The Last Lions contains gorgeous footage, though even for a nature documentary it's graphic in its violence. It also contains what's possibly the most heartbreaking lion-cub scene ever recorded, but don't let that, nor its sometimes soaring levels of anthropomorphism, deter you. by Marjorie Skinner