“Even as we curse war, we become more and more obsessed with it.” Io Fleming's line near the end of the film puts the whole story of Mobile Suit Gundam Thunderbolt: December Sky into perspective. War hasn't done Fleming or his rival Daryl Lorenz any favors—and yet, as this movie progresses, they become increasingly unable to think about anything else. It's both the strength and weakness of this film: the more vivid its depiction of soldiers' wartime suffering, the more humanity our protagonists lose until there's nobody left to root for. In art, music, and acting, this movie is unforgettable. But its story might be a little too dark for its own good.

Who is the protagonist of Mobile Suit Gundam Thunderbolt: December Sky? At first it seems like Io Fleming, the spirited Moore Brotherhood pilot who seems unfazed by the horror around him. After all, he does pilot the impressively designed titular Gundam. But it doesn't take long for this jazz fiend's unhinged streak to come out, both in the way he treats his comrades and the way he taunts his prime enemy, Daryl Lorenz, with the moniker “Peglegs.” So perhaps it's Daryl? A skilled sniper who has given everything to the Zeon cause, including his own limbs, Daryl's vibrant flashbacks give his story the right tragic note. But Daryl is no saint either, making choices to exchange humanity for fighting prowess as the movie progresses. When these two clash, neither of them comes out looking like the good guy.

Daryl and Io's story is told through the most dramatic art style in the Gundam canon. Characters' forms are scrawled with a heavy black pen and plenty of contrast. This startling visual style is driven home further with cameos from some of Gundam's most enduring mobile suits—now seen in stark, gritty realism. Gone are the Gundam's primary colors or the Ball's cartoonish irrelevance. These mobile suits have seen serious action, and the color palette, emphasized by bright red blood splatter, screams “not for kids.” If anything, the characters look older than usual, but that might simply be because a cadre of teens gets shipped in as reinforcements on the Federation side. Far from 15-year-old Amuro saving the day in Mobile Suit Gundam, these kids are not long for this world. It's almost as if December Sky wanted to double down on original Gundam director Yoshiyuki Tomino's core “war is bad” message and make it bloody enough that this time, nobody will get distracted by cool robots and miss the message. (It's worth noting, however, that viewers don't need any prior Gundam knowledge, including of the Thunderbolt manga or OVA, to grasp this plot.)

Honestly, Gundam doesn't get much darker than this. Here in the shoal zone, the Thunderbolt Sector, people regularly lose their lives in horrific ways over something as stupid as a trade route. The dramatic irony is that viewers know this takes place at the end of the One Year War, but for the characters it's a never ending stalemate. They've been promoted to replace their friends, comrades, and lovers who have died. We're talking excessive drug use, disturbing medical experiments, and characters whose souls disappear before our very eyes. The animation doubles down on the drama, focusing hard on blood drops, teardrops, and pupils blown wide from bloodlust, fear, or abject horror. At times, the violence and tragedy feels exploitative, like the movie was trying too hard to drive its point home.

The soundtrack is occasionally the sole light in this darkness. Io loves freeform jazz, and his soundtrack is as wild and unpredictable as the Thunderbolt Sector itself. Daryl prefers pop and country, and these melodies make for a background that fits perfectly for every aspect of his life—jubilant during his childhood flashbacks but more melancholy when paired with the increasingly grim circumstances of his life as a soldier. Sometimes the soundtrack veers in a completely different direction, somehow ranging from an operatic aria to futuristic chiptunes. It's almost unbelievable how amazingly it pulls off this spectrum. I am far fonder of the December Sky movie than the Gundam Thunderbolt manga, and I think its music is the clincher. Instead of the drawn music notes and written lyrics of the manga, the music in this movie feels like a living thing, driving action, character development, and the story together. You can have a scene with no words and no vocals, just the music illustrating the rapidfire choreography of a mobile suit battle, and make it one of the most memorable parts of the movie. Additionally, both dubs are spot on—whether you're listening to the Japanese actors or the American ones, you're getting the same expressive delivery and cadence.

By the end of the movie, our main characters are hardly recognizable—both physically and psychologically—but they've both sunken to each other's level. War may never change, but it has changed these two for the worse, until we no longer have any good guys left. This movie will leave graphic scenes and vibrant action seared across your eyeballs, but it won't leave you with a new favorite character, and it certainly won't have you processing a deeper message than “war is really bad.” It's a stunning musical journey and an impressive exploration in dark visuals. But it's so concerned with illustrating the way war makes monsters of us all to care that by the end, there aren't any humans left.