Exquisitely animated with a plot wound tightly enough to keep you on your toes, this film is the finale to the first season of Demon Slayer, an anime series about a young boy named Tanjiro on a quest to learn how to kill demons and save his sister, who has become a demon. Mugen Train follows Tanjiro and his friends as they board a mysterious train upon which 40 passengers have mysteriously disappeared. There, they encounter a villain who sends his victims into an endless sleep—a neat plot device that uses dreams as vehicles for sentimental vignettes to highlight each character. The action scenes are flawless, even as the emotion sometimes leans toward the saccharine. While the film is best enjoyed after first finishing the series, director Haruo Sotozaki notably walks a neat tightrope, at once creating an exciting stand-alone feature film and a sequel to the existing story. Japanese with subtitles or English dub.