The War of the Rohirrim is an exuberant prelude to one of the most sweeping passages of Peter Jackson's Lord of the Rings films if they were a symphony. To portray the story of Helm Hammerhand and the great battle that established the legend of Helm's Deep, the most recent addition to the expanding canon of Tolkien adaptations transports us to the kingdom of Rohan, decades before the events of The Two Towers. This animated prequel, which Kenji Kamiyama directed, combines explosive action, a visual flair that seems both reverent and surprisingly contemporary, with Tolkien's epic gravity.