Sneha Jaiswal (Twitter | Instagram) Click here for short audio version
Goosebumps! That’s the word I’d use again and again to describe the first episode of the anime ‘The Summer Hikaru Died‘. I can’t remember the last time a psychological-horror anime, or any series really, hit me this hard, this fast. This is easily, one of the best anime series of 2025.
Directed by Ryōhei Takeshita, the anime is based on the horror-manga series by Mokumokuren, a complex tale of teen friendship, death, loss, love, loneliness, and monsters. Schoolboy Hikaru Indo disappears into the mountains for a few days and then returns home seemingly unchanged. But his childhood best friend, Yoshiki Tsujinaka, senses a dark truth: something else came back wearing Hikaru’s face. The imitation is nearly flawless, but every so often, the mask slips in subtle ways unnoticed by everyone else. Everyone except Yoshiki.
Spanning 12 episodes, the first chapter of ‘The Summer Hikaru Died’ starts with a frenzied, tense flashback of teenager Hikaru’s death in the dense forests near his village. Nearly six months later, on a hot summer day, as Hikaru and his childhood best-friend Yoshiki have an ice-cream, the latter finally picks up the courage to confront him.
“You are not Hikaru. Are you?”
In response, an eerie entity partially leaps out of Hikaru’s body, exclaiming it was doing its best to imitate the boy, that it likes Yoshiki and didn’t want to cause him any harm, as long as he promises to keep its identity a secret. The horror elements in the show don’t just stem from the entity’s eerie alien form, but also from the fact that ever since it descends from the mountains in Hikaru’s body, other ghostly entities and misfortunes begin to plague the region too. The locals believe a malevolent being is hiding among them, and Yoshiki wonders if its Hikaru.
Titled ‘Replacement‘, episode one of ‘The Summer Hikaru Died’ establishes most of this in the very first few minutes, setting the pace for the bizarre psychological horror story, where a parallel subplot shows an organization working to hunt entities like the one inhabiting Hikaru’s body. So even though a scared Yoshiki (voiced by Chiaki Kobayashi) wants to hold on to the ghost-like Hikaru (Shûichirô Umeda), there’s a threat of him losing his friend all over again.
What makes the entity more confounding is the fact that it retains all of Hikaru’s memories. Most other school friends are blissfully aware of any change in Hikaru, except for a more perceptive than usual friend called Asako, a cheerful girl, with the ability to sense the supernatural.
‘The Summer Hikaru Died’ centers on Yoshiki’s psychological turmoil, his grief over Hikaru’s death and his desperate attachment to the entity now wearing his friend’s face. As the episodes progress, a strange, symbiotic bond begins to form between them. The entity openly admits its ignorance of its own identity, unsure of what it is, unable to comprehend death, but gradually grows dependent on Yoshiki’s friendship.
The character animation in ‘The Summer Hikaru Died’ stays true to the manga designs, while the overall animation quality feels slightly dated yet still engaging. Yoshiki is tall, with a dark mop of hair and sad eyes that accentuate his serious demeanor, while Hikaru’s cheery personality is reflected in his bright white hair and a cute snaggletooth. The style leans into a more modernist, psychedelic imagery during the horror sequences, especially those depicting violence. The show’s stark contrast between its unsettling supernatural moments and the lighter, everyday school scenes make it visually arresting. The only thing stopping me from giving the anime a full five stars is that, frankly, the animation quality could’ve been better.
The emotional episodes are elevated by their background score and vivid ambient soundscape, filled with the hum of summer, the chirping of birds, and the drone of cicadas. Through sound alone, viewers are transported to the remote Kubitachi village, steeped in the tranquil beauty of the mountains. In its lighter moments, the show makes one yearn for the simplicity of rural life, but when ghosts and eerie entities appear, that same idyllic village transforms into a haunting nightmare.
While there are many interesting characters making their appearances through the anime, the two that standout most are a matronly woman called Kurebayashi Rie, and Tanaka. Rie can sense supernatural things and immediately warns Yoshiki that he is getting close to something ‘dangerous’. At first, she seems like a nutty lady with a bit part, but through the course of the show, she emerges as a major supporting character, who Yoshiki turns for guidance.
Tanaka, on the other hand, looks like he stepped straight out of Jujutsu Kaisen, he’s got that subtle Satoru Gojo-style swagger, friendly yet aloof, and constantly sporting sunglasses (though for entirely different reasons). He arrives in Kubitachi Village to hunt down the entity the elderly locals believe descended from the mountains. In one of the show’s rare comical touches, Tanaka’s sidekick is a pet hamster that helps him sound out spirits.
The conversations between Tanaka and the locals throughout the course of ‘The Summer Hikaru Died’ hint at a dark Indo family tradition of going to the cursed mountains to perform a mysterious ritual. There’s a cult-like sense of kinship, secrecy, and shared understanding among the older locals, who clearly know more about the strange happenings in the region than they’re willing to admit. The slow-burn suspense might be a challenge for impatient viewers, but I thoroughly enjoyed the pace and intrigue of the show.
The second-half of ‘The Summer Hikaru Died’ focuses on the boys’ attempts to understand what the entity really is, so they begin to do research on their village and its myths. Their digging leads them to dark, unsettling secrets about the region, all of it attached to a strange deity called ‘Nonuki-sama’.
Except for the minor glitches in the animation quality, all the other ingredients of ‘The Summer Hikaru Died’ are flawless. There’s constant tension and an ever-present suspense surrounding the fate of the two childhood friends. The voice acting is exceptional: Chiaki Kobayashi, as the emotionally charged Yoshiki, delivers a gripping narration, while Shûichirô Umeda playfully captures Hikaru’s impish charm through lighthearted giggles and laughter.
Yoshiki’s crippling psychological struggles never feel repetitive, serving as a poignant reminder that grief takes its time to fade. Simple scenes where Yoshiki curls up alone in his bed, crying into his pillow, missing his childhood friend, leave powerful impressions in the show. There are pills lying around him, we never see him consuming them, but it is implied he is either taking something to help him sleep, or for anxiety, and stress. It’s not just the summer Hikaru died, but also the summer a part of Yoshiki is lost forever.
Perhaps the most powerful aspect of ‘The Summer Hikaru Died‘ is how it forces viewers to wrestle with an unsettling question: if someone you loved died, could you live with something else wearing their face? The anime doesn’t just stop at Yoshiki’s struggle, it mirrors the same moral dilemma through a tale taught in school, deepening the emotional weight. “Hikaru is gone, that’s not going to change, so even if he’s a fake, I want him to stay,” Yoshiki tells himself again and again, even as he silently carries the truth that the entity isn’t really Hikaru.
The entity, of course, is the most confounding yet oddly endearing presence in ‘The Summer Hikaru Died’, like an alien learning how to be human, who also becomes immediately terrifying when he unveils his true form. But as Hikaru, his childlike fascination with ordinary moments reminds viewers of the simple joys we often overlook: crying at movies, laughing at manga, savoring good food, or lighting up at a village festival. Through Yoshiki, he discovers companionship so profound that it forces him to question his own existence.
“Sometime, somehow, winter melts into spring. That night sky will become dawn tomorrow. Pour all your wishes onto a flock of clouds. And send it away to an unknown future. Without a sound… keep dreaming that dream. And secretly… keep seeking what you seek…”
These are the lyrics of “Shadow of Our Days”, a gentle, nostalgic piano piece Yoshiki and his classmates keep practicing for their school performance, one that Hikaru clumsily tries to learn as well. Its wistful melody echoes the show’s themes of fading youth and fragile friendship. When the choir performs it in Episode 7 of ‘The Summer Hikaru Died‘, the music swells like a farewell, accompanying scenes of Yoshiki and Hikaru spending a quiet day together before returning home to an uneasy confrontation.
From Episode 7 onward, ‘The Summer Hikaru Died‘ ushers in a new chapter in Yoshiki and the entity’s bond. I remember thinking, even with five episodes still to go, that I didn’t want it to end. It delivers the best of both worlds: a psychological horror wrapped inside a tender coming-of-age story, a combination rarely executed this well.
In the final stretch, Kubitachi Village takes on a life of its own, a place soaked in myth, fear, and whispered tales of strange sacrifices and rituals. The mystery of Hikaru deepens: is he a vengeful spirit, a divine protector, or a monster wearing a familiar face? As unease spreads through the region, the boys are caught in a web of truths too vast, and too painful, to untangle. The real horror lies in realizing that not every answer brings peace.
The last few minutes unfold by the sea, where the two friends finally lay bare their thoughts, and the animation and lighting of the water are strikingly beautiful. One moment they’re laughing by the waves, the next they’re a sniffling mess. An intriguing twist about the legendary “Nonuki-sama” the boys had been investigating in the previous chapters of ‘The Summer Hikaru Died’ is also revealed, though the friends remain unaware of it.
The closing chapter brims with emotion, giving Hikaru and Yoshiki a cathartic farewell as they gaze at the shore, uncertain of what awaits them. It’s the kind of ending that makes this season of ‘The Summer Hikaru Died’ feel like a strong standalone story, while still leaving plenty of promise for a season 2. This is undoubtedly among the best anime to come out in 2025.
Watch ‘The Summer Hikaru Died’ on Netflix.
Rating: 9 on 10. Watch ‘The Summer Hikaru Died’ on Netflix.
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