The Lord of the Rings: The War of the Rohirrim

Skippable, and the least seen thing with this name on it. An animated feature directed by Kenji Kamiyama, set about a hundred and eighty years before the Fellowship, telling the story of the king that Helm's Deep is named after. It performed poorly enough that it disappeared from cinemas quickly.

The source is two paragraphs in an appendix, which is both the problem and the licence. There is no novel being adapted here, so the film invents a daughter for Helm and makes her the protagonist, and the invention is the best thing in it: a story about a siege endured by the people inside a fortress rather than won by a cavalry charge.

The animation is the sticking point. It is traditional two-dimensional work over digital backgrounds, made on a budget well short of what the format needs at this length, and the quality varies noticeably between sequences. Some of the snow and the fortress exteriors are lovely; some of the character animation is stiff.

Philippa Boyens, who co-wrote the Jackson films, worked on it, and Miranda Otto narrates in character from the trilogy, so it sits inside that continuity deliberately. Watch it if you want the back story of a place you already know, and expect a modest film rather than an event.