Anime Review: Hikaru ga Shinda Natsu

I have always heard good things about Hikaru ga Shinda Natsu (The Summer Hikaru Died), so when I saw that it was getting an anime adaptation, it was something that was immediately going on my “To Watch” list. Now, we have reached the end of the first season of this psychological horror series, but did it live up to all of the hype that preceded it?

Let’s go!

The Story

Yoshiki is running through the mountains as a group of people is searching for a boy named Hikaru. We see a brief shot of him on the mountain trail with blood covering the left side of his face. Then, we get some abstract colors and shapes that appear to be a sentient being on the move. Fast forward six months, and Hikaru is hanging out with his friend Yoshiki outside of a convenience store. They are there for some ice cream, but all they have is some sort of soda-flavored ice treat. While the two of them are talking, Yoshiki poses a theory… that Hikaru isn’t who he says he is.

At that moment, part of Hikaru’s face transforms into that abstract thing we saw on the mountain. Hikaru has died, and this thing has taken over his body; however, he has all of Hikaru’s memories and personality. Despite having all of that, he has never experienced the things that are in Hikaru’s memory, so when he has something like konbini fried chicken for the first time, he remembers Hikaru having it, but it’s his first time experiencing it.

Despite learning the truth, Yoshiki can’t let go of the fact that Hikaru is gone from his life, so he opts to accept whatever the new Hikaru is as something to fill a void; however, the feeling is somewhat mutual for Hikaru due to a wish the real Hikaru made right before he died on the mountain. The new Hikaru can’t leave Yoshiki’s side and wants to stay by his side to protect him no matter what; however, the true nature of the thing inside of him slips out from time to time, putting that trust in jeopardy.

Despite a few rocky encounters that required some reconciliation, Yoshiki attempts to dive deep into the history of the village to try to unravel what the thing inside of Hikaru’s body truly is. As he continues to dig, the more he uncovers, but the more he cannot understand. Meanwhile, we have Tanaka, a man who is on an investigation from a certain company, drawn to the village by a presence known as Nounuki, and how it could be all connected to the thing inside of Hikaru!

The Characters

Yoshiki Tsujinaka

Yoshiki is typically a quiet boy who keeps to himself. The only thing that gave him purpose in life was his childhood friend Hikaru. When he died on the mountain and came back possessed by something, he instantly recognized the differences and called Hikaru out on not being the real version of his friend. Despite learning the truth, he couldn’t throw the new Hikaru away because he needed Hikaru in his life; otherwise, he would feel as if everything for him would fall apart. He needed this Hikaru to fill a void, so he continued to press forward… in other words, he was in serious denial and delusional to the point where even a monster was good enough to keep things the way that they were before Hikaru’s death. Call it desperation if you’d like, but Yoshiki truly didn’t want to let go, which caused the new Hikaru a bit of pain… once he understood what human emotions were, but Yoshiki is merely one side of a coin in this series.

Hikaru Indou

The original Hikaru was light, cheerful, and always trying to make people laugh and smile. He was a goofball, but that’s what Yoshiki found endearing. He was the sunshine in his otherwise dark and gloomy life. After dying, the new Hikaru simply mimicked what the original Hikaru liked without understanding anything about human emotions. He just had a particular attachment to Yoshiki and didn’t want to leave his side. This feeling only fueled Yoshiki’s attachment to the new Hikaru, creating an endless cycle of needing one another to exist. Of course, we learn a bit about the thing that is inside of Hikaru’s body and how it ties into some of the village’s folklore (especially the dark history of the Indou family). As a character, the new Hikaru eventually learns what humans feel whenever they are sad, angry, etc. This shows that whatever is inside of him is adaptive to his surroundings and to people.

Overall, the new Hikaru is an interesting character. It’s a balance between a terrifying monster whose true purpose is kind of a mixed bag of things. Without spoiling too much, there are many facets as to why it exists, but despite learning some of them, we don’t truly know the full nature of the monster, its true purpose, or where it even originated from. We do know of one of the reasons why it exists, and when it’s revealed, it explains so much about why it was attached to Yoshiki and why Yoshiki fed off of that attachment to fill his void. Hikaru is a very complex, yet captivating character with an insane amount of layers. Definitely, one of the most well-written and well-developed characters of 2025 so far!

Tanaka

There is a lot of mystery surrounding Tanaka. We know that he’s in the village on behalf of a company that, after twelve episodes, still hasn’t been named or detailed. We know that he was sent there to investigate the mystery of Nounuki and to ultimately rid the village of it once and for all. He has some pretty unorthodox methods to achieve these goals, some of which involve using a hamster that he keeps with him wherever he goes. He speaks low and bluntly, but purposefully, never truly revealing too much about himself or his methods. He only offers the promise that he will handle things; however, no matter what situation he finds himself in, he acts as if this isn’t his first time handling dangerous spirits or monsters. He has that seasoned veteran who has seen it all vibe to him. Call it overconfidence or not, he knows what he’s doing and isn’t afraid to jump straight into the fire if need be.

I liked his involvement here in the first season. They built him up to be a threat, but also intelligent, funny, serious, and mysterious at the same time. He is an example of another very layered character with a lot of depth as a result of great writing. In fact, I would go so far as to say that he is my favorite character in this series… especially when they reveal a certain physical aspect to him that makes you wonder how he ended up in that state, to begin with!

Rie Kurebayashi

She’s a minor character, but one not so “background” that she’s worth talking about. Simply put, she is a housewife who can see things that ordinary people cannot. She comes across Yoshiki and begins to worry about him, especially when she gets a glance at Hikaru. I don’t want to call her a Medium, but she’s kind of like that, only not. She just has a gift (or curse, depending on how you look at it) to see the paranormal around her, and she wants to help Yoshiki and Hikaru get to the bottom of Hikaru’s true identity, even if it means putting herself in harm’s way. She does get some development that explains why she does what she does, even if that development is a bit on the grim side. Still, she is an endearing character who just wants to help, making her a great supporting character.

Asako Yamagishi

She’s the final character that is worth noting. She is a classmate and friend of Yoshiki’s alongside Yuki Tadokoro and Yuuta Maki. Yuta and Yuuki are about as “background” as background characters go. They only add some spice when and where they are needed without any true purpose outside of just being classmates and friends with Yoshiki and Hikaru, but Asako, on the other hand, offers up a bit more because, like Rie, she too has a gift/curse of being able to see, or at least, sense things on the paranormal side. She becomes a bit suspicious of Hikaru, and this causes her to end up in a rather unpleasant situation with him.

Despite it, she doesn’t remember much about what happened, and perhaps that’s a good thing, but there is that nagging feeling that she remembers more than she is letting on. Still, she tries to suppose Yoshiki as much as possible, with Yoshiki returning the favor by telling Hikaru not to do anything further to her. Thanks to Hikaru’s infatuation and willingness to protect Yoshiki, he easily grants that wish and promises not to hurt Asako, but that doesn’t stop Asako from becoming suspicious of him. In fact, her suspicions end up as a catalyst for Hikaru to learn and understand what human emotions are all about! Despite being such a minor side character, she does play a pretty important role in Hikaru’s development! Plus, there’s that little, tiny, itsy-bitsy hint that she might like Yoshiki outside of being a friend. It’s never thrown in your face, but there are extremely subtle hints there!

Art, Animation, and Sound

CygamesPictures handled the production of Hikaru ga Shinda Natsu, and I have to say that they did an incredible job with the art production. The backgrounds were absolutely stellar, and at some points, they blended in real-life scenery… especially during the ending and the final episode. There were even moments in Episode 12 where I had to guess whether or not the train ride was real or if it was animated (mainly the scenes of them talking on the interior). It’s hard enough to try to get CGI and traditional animation to blend together, but to make me guess between animation and real life is no small feat. Obviously, the scenes outside of the train were super easy to tell apart from the animation, though.

As far as character designs, I will be honest here… they were hit or miss with me. I liked Asako’s design, and Hikaru had a unique look to him, but Yoshiki just seemed a bit flat, like he was a generic Seinin character. Plus, I wasn’t a fan of a lot of Hikaru’s facial expressions. I understand that they were exaggerated to fit the character’s personality, but it looked a bit too over-the-top at times. That would be my only complaint from an artwork standpoint.

The animation, on the other hand, I felt was quite good. As I said, it’s hard to blend CGI and traditional animation together, and while, yes, the parts where Hikaru showed himself as the monster he truly is were obviously CGI, it wasn’t painfully obvious to where it suspended your disbelief. It meshed very well together and helped enhance Hikaru’s character, rather than subtract from it. Even the parts where it tried to creep into Yoshiki’s body were very well done, as it added to the creep-out factor… something a good horror series should be doing.

As far as the soundtrack goes, the opening song from Vaundy, “Sakai,” had a tremendous balance between horror and alternative J-Rock. I think the clashing motifs symbolized Hikaru perfectly. The horror tones of the song accented the monster inside of him, while the lighter, happier rock moments reflected the old and new Hikaru’s human personality. As far as the overall soundtrack goes, it didn’t truly stick out as memorable; however, it added the necessary ambiance to each scene where needed, blending perfectly into the story and giving you the emotions that you needed to feel at crucial times, so well done there.

Overall Thoughts

Whenever you think of psychological horror shows, you don’t think about Hikaru ga Shinda Natsu, and that’s a compliment. So many shows rely on jump scares or killing off characters left and right in the bloodiest ways possible that they sometimes forget how to tell an incredible story. This show fixes all of that.

In fact, I would go out on a limb and say that this acts more like a slice-of-life mystery than a psychological horror show. A small backwoods village with a haunting past so bad that none of the other surrounding villages want anything to do with it, the legend of a terrifying monster named Nounuki that descended down from the mountain, and the monster that resides inside of Hikaru provide for the horror aspect of the show. The rest of it is filled in with a boy coping with the loss of a friend, using the new Hikaru as an excuse to not let his friend or his memory die, and a monster who is desperately trying to understand what it is and what human emotions are… all wrapped around an exterior threat looking to come and erase it from existence in the most subtle and humbling way possible.

It’s an incredible recipe for intrigue. This show (and series as a whole) took a big risk straying away from what is to be expected from the horror genre, and I have to say that it paid off in spades. What we were given was a very well-written, well-developed, and very interesting story that made you feel the connection to the characters as much as it made you become invested in the mysteries surrounding them.

Do I wish there were more of a horror aspect to the show? Sure… there could have been some tenser, darker moments, but I will say that the moments we did get felt good enough to satisfy that horror craving. Everything from the bathtub scene to almost taking over Yoshiki’s body at school made your heart race, but not in a way that would make you scared, but rather in a way that made you feel tense because the characters you know and have grown attached to could disappear or change forever. It invokes a different set of emotions from the viewer in ways that some horror shows could only dream of achieving.

If you have Netflix, this should be on your watch list. The fact that it’s getting a second season is tremendous, too! I can’t wait to see how the story continues, as the first season left that good of an impression on me!

Go watch this!