A girl named Nono sneaks out of her house in the middle of the night. She makes it through a blizzard and boards a train. She wonders if she was stupid for running away from home. The next morning she arrives in a city. She declares that she’ll become a space pilot no matter what. Some time later, Nono works as a waitress at a restaurant. Three EVO-III Machine Weapon pilots tease Nono about her dream. One of the pilots uses his EVO-III to open the can of wax for her, but he also plays around with her. Another customer, Lal’C Mellk Mal, gets up to leave. She takes a seal off her forehead and a giant hand shoots out of her shadow. It frees Nono from the EVO-III and smashes through the roof. Nono stares in awe as Lal’C leaves. The Captain identifies her as a Topless, which the owner tells Nono is a real space pilot. Nono chases after Lal’C, calling her “big sister.” She thanks her, and says she’ll help her out next time. Nono asks if she a space pilot, and Lal’C explains that she’s a member of Fraternity’s Space Monster Interception Squad. Nono says she wants to be a space pilot so she can protect everyone and become a “Nono-Riri.” Lal’C wraps her scarf around Nono and slaps a seal on her forehead. The seal breaks, and Lal’C says Nono can’t join. She says they don’t need anyone who isn’t a Topless. Lal’C watches the sunset and is joined by a cat. Tycho Science, speaking through the cat, asks her how it feels to be back on the ground, but Lal’C doesn’t like it. Lal’C says the Serpentine twins’ predictions had been off lately but Tycho says she predicted it as well, and a suspicious meteorite was confirmed. A Space Monster is definitely there. The pilots find Nono sulking and tell her that the restaurant owner is out looking for her. One of the pilots finds a centipede creature and yanks on it, causing a bigger creature to come out of the water. The EVO-IIIs attack it, but are easily defeated. A damaged arm goes flying at Nono, but Lal’C saves her. Lal’C comments that she’s never seen that type of Space Monster before. She summons her Buster Machine, Dix-Neuf. Lal’C boards it and activates her Exotic Manoeuvre, powering up Dix-Neuf. Lal’C beats up the Space Monster, and blocks its beam attack. The restaurant owner arrives in her van and tries to get to Nono. The Space Monster lands on the van, trapping the owner inside.
Nono tries to lift up the Space Monster’s limb, but the owner tells her to run away. Nono says Nono-Riri never gives up. Nono’s eyes start glowing and she lifts the limb up. Nono gets caught on the limb when the Space Monster wakes up. Dix-Neuf grabs onto the Monster as it blasts up into space. Now in orbit around Mars, Lal’C sees Nono’s charred body on the Space Monster. In a fit of rage, Lal’C destroys the monster with a Buster Beam. Lal’C is surprised to see Nono, perfectly fine, float towards her. Nono thanks Lal’C for saving her again and Lal’C wonders what Nono is. Lal’C returns to the Satellite Base Meganebula with Nono. They are met by Tycho, Nicola Vacheron, and Casio Takashiro, the latter identifying Nono as an android. Four months later, Nicola speaks to the Serpentine Twins, Piaget and LeCoultre, and asks them why they ordered him to look after Nono. They say it’s because the Space Monster likely came for Nono and tell Nicola to bring Nono to Titan. On the way to Titan, Nono writes a letter to her old master about her time at The Fraternity. Lal’C takes the letter from her and Tycho notes now Lal’C has been smiling a lot recently. Casio introduces Nono to the other pilots on the shuttle but they doubt an android can be a Topless. They add that she doesn’t have a Buster Machine either. A Geological Survey Ship arrives on Titan. They head to an excavation site and three scientists discuss what’s buried there. One suggests that it’s an alien Buster Machine from Sirius. The ship runs into the Serpentine Twins’ Buster Machine, Quarante-Deux. Nicola, who is on the survey ship, says they have to leave the airspace. They arrive at a base and the crew unloads equipment. They see Nhan Nuok Cham, Roy Anyan, Pasika Pesca Persicum, Gurka Kuksis, Tycho, and Lal’C enjoying themselves at a pool. Nicola tells the crew not to wander around and goes to join the other Topless. Later, while changing, they discuss the Fluctuating Gravity Well and how it could be a single digit Buster Machine. They wonder if Nono will be the pilot, and comment how Lal’C’s score has increased because of Nono’s help. Lal’C said that’s not true, but runs into Nono when she opens the door. The other Topless tease Nono, saying she should just go back to the country and get married. Nono scrubs the pool and wonders if she could get Lal’C to acknowledge her if she had a Buster Machine too. Tycho and a hidden Lal’C listen silently. The Serpentine Twins eat a feast of meat, and Nicola is disgusted by the smell when he enters the room. Nono watches the Buster Machines and thinks that if she had one, she’d become a Nono-Riri. Nono heads down into the excavation site. The Serpentine Twins explain that the terrain is made from the bodies of dead Space Monsters that tried to bury the Fluctuating Gravity Well. Despite that, it’s still alive and is becoming more active. They add that if they can control it, they’ll have nothing to fear. Nicola says he doesn’t have much time remaining. The Twins tell him not to worry since he knows their true age and the secret behind it. They offer him a piece of meat. Nono reaches the bottom, but she gets a weird feeling. The alarms then go off. She is sent before the twins, but they tell her not to worry about it. They tell her about Buster Machine Trente-Trois, which had gone missing but was discovered on Pluto. They say Nono should make it her own. Tycho tells Lal’C that Nono is going to Pluto and suggests that it’s Lal’C fault. Tycho also notes that the Buster Machines have been acting weird since they arrived. Lal’C says that’s not possible since she knows everything about Dix-Neuf. Tycho says a Buster Machine might open up to some one like Nono, and Lal’C notes that she sounds like Casio.
Casio tells Nono it’s time for them to go. Nono prepares to board her ship, but Lal’C tells her she should just stay. The ship takes off and Nono says she feels very far away from Lal’C, but she’s going to close the gap. Lal’C thinks back to how she used to show Nono pictures from Earth. Lal’C figures that if Nono-Riri was a Buster Machine pilot, she must have been a Topless. In that case, Nono could never become one. Lal’C meets Tycho in the laundry room, and Tycho tells her that she heard from Casio. He said that they were almost at Pluto and that Nono was doing just fine. All the Buster Machines are positioned around the excavation site as the Serpentine Twins use Quarante-Duex to operate on the Fluctuating Gravity Well. At the same time, a massive number of Space Monsters come out of the Red Milky Way. The Space Monsters arrive at Titan, and the Buster Machines intercept. Half of the Space Monsters break off and head towards Pluto. Nono and Casio head towards Pluto, but are attacked by the Space Monsters. The Serpentine Twins note that the Space Monsters went after Nono as planned. The Fluctuating Gravity Well awakens. The Buster Machines continuing fighting but are overwhelmed by the numbers. The Twins tell them they’ve done well and the Fluctuating Gravity Well beings to surface. Casio and Nono approach Trente-Trois, but their shuttle crashes. The Fluctuating Gravity appears, and the Space Monsters attack it. The Gravity Well fires a blast that wipes out most of the Space Monsters. The Twins reveal that it is not a Buster Machine, but an ancient Topless. Nicola almost vomits, realizing where the meat he ate came from. Casio and Nono continue on foot, Casio telling Nono that piloting a Buster Machine is a frightening thing and that she doesn’t need it. He adds that Lal’C doesn’t think so either, and Nono recalls how Lal’C invited Nono to her house on Earth. Casio says that all Topless have are the Buster Machines, and that once they loose them, they can’t find a reason to live. He says Nono-Riri was probably the same. Nono says he’s wrong. Casio says he’s still a Topless so he’ll use Trente-Trois, but once they arrive there, they see that Trente-Trois is just a skeleton. The Space Monsters gather on the opposite side of Titan. The Fluctuating Gravity Well turns on the Twins, firing a blast that kills them and travels through the moon, destroying the Space Monsters on the other side. Nhan is killed by rubble and the Gravity Well continues firing. Gurka and Pasika are also killed. Lal’C asks Dix-Neuf what the Gravity Well is and she realizes that it is a true Space Monster. She wonders what they’ve been fighting against up until now. Back on Pluto, Nono is surrounded by Space Monsters and some how hears Lal’C getting hurt. Nono’s hair glows red and she creates a singularity in her hands. She grabs it and she and the Space Monsters disappear. On Titan, the Fluctuating Gravity Well prepares to finish Lal’C and Tycho off, but Nono warps out in front of them, absorbing the Gravity Well’s blast. Nono introduces herself as Buster Machine #7. A group of Space Monsters, actually known as the Buster Corps, warps out behind her and attacks the Gravity Well. Nono says that she was an idiot because she didn’t realize a true Nono-Riri has a Buster Machine in her heart. The Fluctuating Gravity Well charges at Nono, but she uses her Buster Beam Slash to cut it, and Titan, in half.
Lal’C and Tycho are committed to a hospital on the planet Kaminatsuki, where Lal’C muses on how their situation has changed. Chief of Staff Niigo explains to a group of individuals the Black Hole Exelio, the black hole created by the Exelion’s destruction, and how humanity had sealed themselves away in the Sol System using unmanned Buster Machines. These Buster Machines continued to evolve and ironically began to resemble Space Monsters. Eventually they began to sense the same thing from humanity as they did the Fluctuating Gravity Wells, namely the Topless. Nono visits Lal’C and Tycho, and talks about all the tests she’s undergone and how she gets whatever she asks for. Nono says she might even get to go to Earth and reminds Lal’C of their promise to see skylarks at her house. Lal’C makes an origami crane from a wrapper and gives it to Nono. On the battleship Karakoram, an admiral named Dhorasoo is informed that a new Fluctuating Gravity Well might emerge from Black Hole Exelio, so his fleet launches. Nono and Lal’C goes with them and Lal’C laments that everyone believes Nono will save them, so there is no need for her to be there. She also reveals that Nicola passed his expiration date and went home. The fleet encounters a massive wall of Buster Corps that Nono has clear a path through. Niigo comments that Nono is like their queen and reminds Lal’C that Nono is the one who had her brought along. They arrive at Exelio where many Buster Corps units try to cover cracks in the black hole. However the Fluctuating Gravity Well continues to try and break free so Nono tries to seal the cracks with micro black holes. The fleet prepares to support Nono and Lal’C is told to leave the bridge. The Karakoram fires its Gravitron cannon but space gets distorted and the beam veers away. The gigantic Fluctuating Gravity Well, larger than Earth, emerges from the black hole and Nono attacks it but her beam is ineffective as well. The Karakoram is severely damaged and Niigo suggests an evacuation. Lal’C heads to the last escape pod, but the pod is destroyed before she can reach it. Lal’C attempts to take off the headgear sealing her Topless powers and berates herself for being pathetic. She releases Nono was the amazing one from the very beginning, but Nono arrives and admits to being jealous of Lal’C being similar to Nono-Riri. She says that Nono-Riri was just a normal girl and makes a key to unlock Lal’C headgear. Lal’C realizes Nono is shaking and that Lal’C herself is the one who has changed. Nono removes Lal’C’s seal and she summons Dix-Neuf. Dhorasoo thinks the situation is hopeless, but Lal’C tells him she’s going to hit the Gravity Well with Jupiter 2. Niigo says no human can do that, but Lal’C says she can do it if she’s with Nono. Lal’C activates her Exotic Manoeuvre and a giant hand grabs the remaining core of Jupiter 2. The core warps to where she is and Lal’C throws it at the Gravity Well.
The impact reveals the rest of the Gravity Well’s body, showing that it didn’t emerge from Exelio but absorbed it instead. The Gravity Well prepares to warp, and Niigo suggests having Nono turn Jupiter 2 into a black hole to destroy it. Dhorasoo says it’s a kamikaze attack and Lal’C tells Nono that they’ll go together. However Nono decides to leave instead and the Gravity Well warps away. The Buster Corps begin to gather together as Lal’C screams Nono’s name. Some time later, Lal’C is welcomed to the Imperial City of Lunar Tokyo by the governor, who apologizes for not organizing a welcome parade. He explains that like Earth, the Moon has been evacuated. He says it’s time for Earth rise, but the ultra large scale ether-accelerated assault weapon Douze-Mille is in the way. Niigo speaks to the elders of the Privy Staff Council and explains that over the past six months the Buster Corps surrounding the solar system have vanished. He adds that the body they had been gathering to form had recently vanished as well. The elders ponder about Nono, but Lal’C enters and says to forget about her. The elders ask if mankind must go so far to survive, and Lal’C says that sacrificing the Earth is their only hope. They entrust the key to Douze-Mille to Lal’C and she leaves afterwards. Niigo asks if it’s okay because Topless could become humanity’s new enemy but the elders say they prefer it to fighting monsters. A man named Hatori and Nicola watch the Buster Machines gather and Hatori asks if Nicola feels betrayed by them. Nicola says that Topless are just batteries to be used up and tossed away. Casio chats with Tycho, who tells her he tried to meet with Lal’C but got a black eye for his troubles. Tycho says that’s to be expected since there was an assassination attempt on Mars and not even Tycho could meet her after that. Lal’C gathers all the Topless and has them take a picture together. Tycho gives her a message from Casio but also notices that Lal’C has a fever. Two months earlier, Lal’C had visited the man who had found Nono and he recognized her right away. They chat, and he says that Nono liked Japanese food because Nono-Riri was a traditional Japanese girl. Lal’C says apparently Nono-Riri was some one who had saved the Sol System in the past and the man wonders if it was the same for Nono. He wonders what part of the Sol System Nono was created to protect and why she was given human form. He says if Nono-Riri really was a normal girl, then she would need a friend and that Nono was probably happy to have met Lal’C. The Exelio Fluctuating Gravity Well’s warp out is detected, and Niigo explains to fleet commander Zaha Hadid that the plan is to knock the Gravity Well into the black hole using Douze-Mille. Hadid says they’ll buy time for Lal’C and laments how the Topless are barely older than her own daughter. Exotic Manoeuvres lose effectiveness near the Gravity Well, so Tycho tells everyone to stay as a group. Gravity Well grunts appear and the Topless engage them before the Exelio Gravity Well, now in its larger third evolution form, appears.
Lal’C prepares Douze-Mille for activation and Hadid tells her to bring it, and the pilot, back in one piece. Lal’C removes her seal and Dix-Neuf starts up Douze-Mille which has converted Earth into humanity’s ultimate weapon. Douze-Mille launches, moving Earth on a collision course with the Exelio Gravity Well. Niigo says their victory is assured but Hadid hopes Lal’C feels the same way. Lal’C activates the Exotic Drive and Earth accelerates to sub-light speed. In transit, a giant machine resembling Nono warps out. Identifying itself as Diebuster, it proceeds to try and stop Douze-Mille. Lal’C turns part of Douze-Mille into a giant Buster Machine and attacks Diebuster. She tells Nono that humanity’s battle has nothing to do with her, and admits that if Nono had stayed her friend, Lal’C wouldn’t have been afraid of losing her Topless power. She says she wanted to be called Lal’C rather than big sister but before she can hit Diebuster again, Douze-Mille breaks apart. Lal’C notes that she can’t hear Dix-Neuf’s voice anymore and Tycho realizes Lal’C has lost her powers. The Earth stops moving and Diebuster attacks the Exelio Gravity Well with an Ultra Lightning Kick and then follows up with a Buster Collider attack, but it doesn’t work. Diebuster then fires a Buster Beam point blank, but the energy wraps around the black hole and is fired back at Diebuster instead, making her crash into the Moon. The Gravity Well fires on the Earth, but Diebuster sacrifices both arms to block it. Diebuster continues taking damage while Lal’C remembers Nono saying that Nono-Riri was just a normal girl. She hears Nono say her name, so she heads into Dix-Neuf’s emergency spinal passage. A shockwave makes her lose a tooth, but Lal’C continues on until she gets to the horn in Dix-Neuf’s eye. Dix-Neuf pulls the horn out himself, unlocking the true cockpit located in his brain. Lal’C enters the cockpit as Diebuster is damaged further. Lal’C changes into the Top Squadron uniform that was in the cockpit and has Dix-Neuf tear open his chest. He takes a degeneracy reactor from one of the Buster Corp machines and puts it inside his chest, allowing him to assume his true form as Buster Machine #19. Lal’C asks Nono what she’s doing and tells her that power isn’t based on the size of the body, but the strength of the heart. She says it’s about hard work and guts, and Nono flies out of Diebuster’s remains. Together they perform the Lightning Double Kick and destroy the Exelio Fluctuating Gravity Well. At the same time, they crack the black hole which threatens to cause a second Big Bang. The remains of the Buster Corps form giant hands and contain the black hole. In the Polydimensional Space, Space-Time Censor Room, Nono tells Lal’C what she imagines visiting Lal’C’s house would be like before saying that Nono is going to take the singularity and give Lal’C her singularity in exchange. The giant hands collapse in on themselves and explode harmlessly. Lal’C wakes up in Casio’s arms and opens her hand to find an origami crane.
Ten years later on Earth, Lal’C is working as an environmentalist. She talks on the phone with Tycho who is on Pluto and about to leave to protect a diplomatic envoy to the Sirius star system. Tycho asks about some festivals and notes that they’re too old to believe in wishes, but Lal’C tells her that an observatory has conformed something. Lal’C makes her way to the top of a hill and watches as all the city lights shut off. She looks to the stars and sees a moving light, saying that Nono-Riri is coming back. That night, Buster Machines #1 and #2 along with their pilots returned home.
For this movie, episodes two and three are done away with completely and that works to its benefit. I’m not very fond of episode 2, and episode 3 was pretty pointless. The story is still great without them. One advantage this movie has is that they were able to animate new footage to smooth over the transitions. As such, it’s better as a movie than the Gunbuster one is. I could actually recommend it over the OVA for anyone that would like a more concise story. The OVA is still worth checking out, though.