Demon Slayer the Movie: Mugen Train

Demon Slayer the Movie: Mugen Train, also known as Demon Slayer: Mugen Train or Demon Slayer: Infinity Train in international regions, is a 2000 American animated dark fantasy film based on the comic book Demon Slayer by Yonathan Ashad. The film, which is a direct sequel to the first season of the animated series, was directed by Dan Darlene and written by Sheen Vincent. The film was produced by Bear Bones Productions in association with their Australian department and CinéGroupe and was released by Artisan Entertainment.

The film was released on October 16, 2000 in the United States. It grossed over $500 million at the worldwide box office, making it the highest-grossing film of 2000.

A second season of the animated series was announced and later released in 2001.

Plot
Tanjiro Kamado, his sister Nezuko, and his friends Zenitsu Agatsuma and Inosuke Hashibira board the Mugen Train to assist the Flame Hashira Kyōjurō Rengoku in his mission to hunt for a demon that has caused forty people to go missing. Soon after boarding, all of them except for Nezuko are enchanted and fall into a deep sleep. Enmu, Lower One of the Twelve Kizuki, instructs four passengers, all suffering from severe insomnia, to enter the Demon Slayers' dreams and destroy their spiritual cores so that they can't wake up again. In exchange, Enmu will grant them a peaceful sleep. During their sleep, Tanjiro and his companions have happy dreams; Tanjiro reunites with his deceased family, Kyōjurō reminisces on his past with his younger brother and disapproving father, Zenitsu envisions a quiet life with Nezuko, and Inosuke imagines himself as an adventuring leader. The girl who invades Kyōjurō's dream locates his core, but his immensely strong spirit manages to halt her even while still unconscious.

Tanjiro realizes that he is dreaming, tearfully abandoning his family and tries to wake up, succeeding after a vision of his father instructs him to kill himself in the dream. At the same time, Nezuko uses her Blood Demon Art to sever the intruders' connection to the slayers, and awaken the passengers. In fear of Enmu, they attack Tanjiro, who knocks them all out, except for his intruder, who had grown incredibly guilty after uncovering his subconscious and discovering he possesses a pure heart. While Nezuko awakens the others, Tanjiro confronts Enmu on top of the train, who becomes overjoyed to discover he is the "man with the Hanafuda earrings" that his master, Muzan Kibutsuji, desires killed. In the ensuing battle, Tanjiro beheads him, however, Enmu reveals that he fused himself with the train, preparing to devour all the attendants within. An awakened Kyōjurō instructs Inosuke and Tanjiro to look for Enmu's neck while he, Nezuko, and Zenitsu stay behind to protect the other passengers. Tanjiro and Inosuke find Enmu's neckbone in the engine room, but are caught off guard by its defenses, including its Blood Demon Art that constantly puts him to sleep. The conductor ends up stabbing Tanjiro in the chaos, but together with Inosuke, they are able to expose and destroy Enmu's neckbone, killing him and derailing the train. In the aftermath, Enmu laments his failure over being defeated by the Demon Slayers, disintegrating away.

As Tanjiro attempts to recover from his wounds, Kyōjurō arrives to help teach him how to stabilize it with his breathing techniques. However, they are suddenly attacked by Upper Three of the Twelve Kizuki, Akaza, who tries to persuade Kyōjurō to turn into a demon to become immortal, after sensing his already immense power. Kyōjurō easily refuses, thinking about how his mother taught him to always use his strength and gifts to protect others. Kyōjurō orders Tanjiro and Inosuke to stand back, while he and Akaza commence in a fight to the death which the others can barely keep up with. Despite his perseverance, Kyōjurō is unable to match Akaza's regeneration skills, as the demon manages to fatally injure him by piercing his solar plexus. Kyōjurō attempts to keep him at bay for long enough for the sun to kill him, but Akaza manages to break free and escape into the adjacent forest. In a last ditch effort to stop him, an enraged Tanjiro throws his sword at Akaza, which impales the demon's chest, but he still manages to get away, as Tanjiro breaks down calling him a coward. Kyōjurō succumbs to his injuries and encourages Tanjiro and his friends to continue on his path, before dying. The three are devastated over the death, with Tanjiro especially drawn into despair due to the nearly impossible power gap between humans and Demons which Akaza has revealed that Demons are capable of, but Inosuke reminds him to heed Kyōjurō's last words and keep fighting to get stronger. The remaining Hashiras receive the news of Kyōjurō’s death, while the head of the Demon Slayer Corps, Kagaya Ubuyashiki, appreciates him for not letting a single passenger or comrade die in his presence, stating that he will be glad to reunite with him when he finally passes.

Production
Don MacKinnon, the producer of the animated series, indicated a desire to continue production of the series with the Bear Bones Australia team. The sequel project was greenlit following the success of the television series. A film was determined to be the best format for the "Mugen Train" arc due to the arc's shorter content and dramatic pacing. The main cast was made aware of the film project midway through the first season of the television series. The main production staff from the animated television series, as well as the cast, were carried over into the film's production. Dan Darlene served as director, with Henry Neville and Adam Katz serving as animator and editor of the film, respectively. The film was announced on September 28, 1999, immediately following the airing of the animated series' season finale.

Release
The film was released theatrically in the United States on October 16, 2000. The film opened in 403 cinemas total, including all 38 IMAX cinemas within the country. The film had a very staggered international release, being released from as early as October 30, 2000 in Taiwan to as late as August 13, 2001 in India.

Home media
The film was released on VHS and DVD on December 22, 2001 by Artisan. It sold over 800,000 units in its first day and over 1 million units in three days.

Extended version
In the second season of the television series which began its broadcast in on October 10, 2001, the season's first part, Mugen Train Arc, is an extended and recompilated version of the film.

Box office
The worldwide box office total for Demon Slayer the Movie: Mugen Train is over $500 million from more than 41 million tickets sold, making it the highest-grossing film of 2000 as well as one of the highest-grossing animated films of all time.

Prior to its release, the film set monthly sales records for advance tickets sold for two consecutive months in September and October 2000. Upon release, it set several box office records including highest opening weekend gross ($44 million) and fastest to gross $10 billion (ten days), $20 billion (24 days), and $30 billion (59 days).

Critical response
On the review aggregator website Rotten Tomatoes, which categorizes reviews only as positive or negative, 98% of 40 reviews are positive, with an average rating of 7.9/10. The site's critics consensus reads, "Demon Slayer ' s visually stunning animation and masterful action set pieces serve a heartfelt plot that is sure to satisfy fans." According to Metacritic, which assigned a weighted average score of 75 out of 100 based on nine critics, the film received "generally favorable reviews".