Sir Michael Hordern’s familiar voice establishes the story’s setting as he recounts an old legend concerning the rabbit—explaining not only how it gained its white tail, powerful hind legs, and swiftness but also highlighting its weaknesses: other creatures are eager to eat it. After many years pass, a warren faces problems due to being too crowded, with humans taking over more of their land and leaving them little space. "Hazel" proposes that the group start a new settlement, but the leader angrily rejects this idea. Along with “Fiver,” they leave anyway, only to soon find themselves confronting another colony led by the intimidating "Woundwort," who maintains control through force. I’ve always felt Richard Adams's novel had an Orwellian quality, and choosing such a gentle and mild-mannered animal as the focus for this intense examination of societal breakdown is even more striking, because it turns out they too have a social structure, a pecking order, and their very own version of a secret police force. The animation is beautiful to look at. Both the lightheartedness and brutality of events are portrayed quite vividly as the story progresses. Art Garfunkel’s song "Bright Eyes" isn't used as much as I thought it would be, but its inclusion powerfully underscores what “Hazel” and his companions long for. The ending feels just right, even though it does seem to confirm the survival-of-the-fittest mindset that these animals are attempting to avoid—whether they have four legs or two.

Source on TMDB