Before it begins, cocoon – One Summer of Girlhood tells its viewers that what they’re about to watch is a work of fiction. However, the film also makes it clear that events similar to what occurs in its 64-minute runtime have happened, or still happen this very day. It’s a warning that I took to heart while watching this adaptation of Machiko Kyo’s manga, as reading her original works brought to mind stories I’ve been told about World War II. Just as Grave of the Fireflies showed us the horrors and struggles of surviving and succumbing to a war-torn country, cocoon – One Summer of Girlhood does the same for those who are on the sidelines helping their allies.

Brought to life by Studios Ghibli veterans Akihiko Yamashita and Shinji Otsuka, cocoon places its focus on friends San (Marika Ito) and Mayu (Hikari Mitsushita). Originally attending school, the two friends soon find themselves swamped with nursing work when war breaks out. In a flash, their tranquil days are gone, as they’re surrounded by bomb fire, dead or dying soldiers, and a bleak future. When it becomes too much for the students to handle, they are told to run to the south side of the island, in hopes that safety can be found there.

Just as the manga did, the pacing between peace and chaos is done very well. You see how much San and Mayu enjoy their time together, as well as how they interact with their classmates. They learn about silkworms, and how their silk is harvested for human usage. However, it soon becomes clear that San, Mayu, and the rest of the classmates have more in common with the silkworms than they thought. And when the bombs drop and the injured soldier count rises, they soon find that they’re being pushed to the brink of death to offer any sort of aid they can.

When the film shifts into escape mode, that’s when the more harrowing parts of cocoon emerge. It’s when San, Mayu, and the rest attempt to run through an abandoned village to reach their destination when one’s heart sinks to the lowest part of their stomach. The imagery of flowers replacing blood in this scene adds a more chilling feeling than a beautiful one, as the screen splatters with color with the sound of painfully screaming youth. And from then on, blinking and breathing while watching this film becomes next-to-impossible.

All of it is captured strongly by studio Sasayuri, which only has a handful of production assistance credits as of this writing. However, with the leadership of Yamashita and Otsuka, the animators bring about something as Ghibli-esque as they can. The nature, the character designs, and even the colors all bring about a 1980s Nausicaä/Castle in the Sky aesthetic to Kyo’s original manga. Composer Kensuke Ushio (The Dangers in My Heart) also contributes a very Hisashi-like sound to the film soundtrack, only with a more minimalistic approach to the melodies that adds a lot more tension to what’s happening onscreen.

Even if it’s not a true story (despite it being influenced by the Himeyuri students), cocoon – One Summer of Girlhood makes it feel real nonetheless. The quiet moments are but bookends for the most horrible and nerve-wracking things you could put a young teenage girl through. And when these characters are trapped like silkworms in a pot, one can’t help but feel like they’re also stuck in there, just waiting for the water to boil. It may only last just over an hour, but cocoon – One Summer of Girlhood delivers a lifetime of morals and heartache in a time when war still happens on an unfortunately daily basis.

English subtitled version observed for review. Promotional consideration provided by Grace Liliano of GKIDS and Alexandra B’Llamas-Reynoso & Annabella Penchishen of 42West PR. In US theaters September 4th!