IN GENERAL, television in the last 20-odd years has improved markedly—but it hasn't done so without exception. Along with history, food, and travel, plenty of channels allegedly devoted to an interest in wildlife have devolved into sensationalized reality pap. Why animal lovers would want to watch back-to-back episodes of animals attacking humans, or travel buffs submit themselves to endless reels of far-flung "travel nightmares" is almost beyond imagination. (Maybe it's to cure themselves of any aspirations beyond the TV room?) So when an honest-to-god nature documentary happens, true believers have cause to rejoice.

Actually, hold up on that rejoicing: 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 narration from an occasionally eye-roll-inducing Jeremy Irons, we're reminded that many of their challenges are outside normal circumstances.

Made by a husband and wife team of explorers-in-residence at National Geographic (Dereck and Beverly Joubert), 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. The Jouberts are the real deal, and the lions they film deserve your, and the world's, attention.