Infinity Castle Solidifies “Demon Slayer” as Anime’s Ultimate Cinematic Triumph

If you’ve managed to avoid Demon Slayer: Infinity Castle spoilers on X (formerly Twitter), that alone is an achievement. For everyone else, the buzz has been impossible to miss. The question is whether the film matches the hype — and it does. Infinity Castle doesn’t just meet expectations; it surpasses them with its stunning animation, emotional depth, and battles that confirm Demon Slayer’s place among the most celebrated anime franchises.

Produced by Ufotable and distributed by Crunchyroll in partnership with Sony Pictures Releasing, Infinity Castle is a direct sequel to the anime, picking up where Season 4 left off.

As a refresher, Season 4 ended with Muzan confronting Ubuyashiki, the master of the Demon Slayer Corps. Even though he was already at death’s door, Ubuyashiki managed to buy the slayers precious time to take down Muzan once and for all by sacrificing himself and his family. Just as they had the chance to sever Muzan’s head—thanks to Tamayo and Yushiro, since severing a demon’s head is the only way to prevent regeneration—he transported them into his own personal domain: the Infinity Castle, an intricately structured minefield where both the Lower Rank and Upper Rank demons reside.

This sets the stage for the film. Most of the battles unfold within the Infinity Castle, and ironically, despite trapping Tanjiro, Zenitsu, the Corps, and the Hashiras inside, Muzan is absent for much of the story. A good portion of screen time is spent searching for him, as Kiriya, Ubuyashiki’s son and new Corps leader, spares no effort. He sends out his crows to scour the castle, deliver messages, and coordinate movements in the fight against Muzan’s demons.

The film divides its core battles into three pivotal arcs: Shinobu (the Insect Hashira) versus the Upper Rank Two demon Doma; Zenitsu versus his former senior colleague, Kaigaku; and Tanjiro and Giyu’s desperate fight against the formidable Upper Rank Three demon, Akaza.

Each arc is packed with emotional weight. Shinobu’s battle is seething with rage, as she confronts the demon who killed her sister Kanae. Zenitsu, long viewed as the weak link, finally proves himself by unveiling a self-created Seventh Form of Thunder Breathing, shocking Kaigaku, who assumed he had only mastered the First. Meanwhile, Tanjiro and Giyu’s clash with Akaza is the most gripping of all—secrets are unearthed, the past is unlocked, and Tanjiro taps into the Transparent World, awakening a new power. Akaza, despite regenerating even after being beheaded, is finally defeated by the pair.

Ufotable, renowned since the Fate series for its meticulous detailing, pushes its artistry further here. The Infinity Castle itself is a marvel—hand-drawn with intricate layers, shifting architecture, and surreal movement designed to disorient slayers and demons alike. These details were transformed into breathtaking animation that set the stage for key visuals. Anime is often praised for elaborate world-building, and this film continues that tradition flawlessly.

The battles themselves are spectacles. Shinobu’s fight bursts with vivid colors, butterflies, and floral motifs that mirror both her powers and Doma’s flamboyant yet nihilistic nature. Zenitsu’s battle is shrouded in darker hues, signifying his evolution into a more dangerous and self-assured demon slayer. Tanjiro and Giyu’s fight with Akaza blends light and shadow, symbolizing the balance of truth, pain, and revelation.

Beyond the spectacle, the film skillfully blends the past and present. Doma’s upbringing in a cult explains his allegiance to Muzan. Shinobu’s struggles with self-worth reflect her constant battle to measure up to Kanae. Zenitsu’s history of bullying feeds into his determination to grow stronger. Kaigaku’s arrogance, born from being revered as a skillful slayer, ultimately led to his betrayal of the Corps. Tanjiro’s father’s lessons in the Hirogami Kagura dance—a sacred Sun Breathing technique passed down in the Kamado family—help him unlock the Transparent World at a critical moment. These layered histories ground the characters and propel the plot forward.

The most poignant backstory, however, belongs to Akaza. Over thirty minutes of screen time unravel his tragic past, reframing him not merely as a villain but as a victim of circumstance.

Born Hakuji, he grew up poor, stealing to survive and marked with blue tattoos branding him a repeat offender. His encounter with Keizo, a kind mentor, changed his path. Hakuji abandoned crime, fell in love with Keizo’s sick daughter Koyuki, and planned a future with her—until she was poisoned by the jealous villagers. Consumed by rage, he slaughtered her killers, setting him on the path to demonhood when Muzan appeared. Akaza’s arc is presented almost as redemption—allowing him to die with a sense of release. His story reminds us that monsters are often created, not born, making him the unexpected scene-stealer of Infinity Castle. However, whether or not Akaza is forgiven—knowing his tragic backstory—for slaying Rengoku in Mugen Train is left to individual perception.

The film is a rollercoaster of emotions. Joy, grief, anger, and pain pour from every frame, making it one of the most emotionally resonant anime showcases of the decade. Ufotable, Crunchyroll, and Sony took a bold risk releasing it internationally after its success in Asia—and the gamble paid off. Infinity Castle has already grossed $555 million worldwide, overtaking Mugen Train’s $517 million to become the highest-grossing anime film of all time in under a month. At this pace, it could enter the billion-dollar club before year’s end. Why the success? Because Ufotable has cracked the code: blending fan loyalty with universal emotional appeal.

Still, the film leaves pressing questions unanswered for anime-only viewers. Will Tamayo survive before Muzan consumes her? What role will Nezuko’s evolving powers play? What is the link between Tanjiro, Tanjuro, and Kokushibo, the six-eyed Upper Rank One demon? How did Kokushibo meet Muzan? And is the Infinity Castle truly endless? Most importantly, will Muzan ever be destroyed? These lingering mysteries build anticipation for the next two entries in Ufotable’s planned trilogy.

Infinity Castle is still showing in cinemas worldwide.

Release Date: July 18, 2025 (Japan), September 12, 2025 (International)

Runtime: 2 hours and 21 minutes

Streaming Service: None. Cinematic Release

Director: Haruo Sotozaki

Cast: Natsuki Hanae, Akari Kitō, Hiro Shimono, Yoshitsugu Matsuoka, Tomokazu Sugita, Saori Hayami, Mamoru Miyano, Akira Ishida, and Toshihiko Seki