|Please note that this is the Gundam Wiki's article on the final episode of the first season of Mobile Suit Gundam 00; if you are looking for the article on the main protagonist of Mobile Suit Gundam 00 then you should head to Setsuna F. Seiei.|
Setsuna is the twenty-fifth episode and the season finale to the first season of Mobile Suit Gundam 00
Setsuna attacks the Alvatore but dodges a number of beam shots. Lasse suggests hitting the remaining parts of the combat container to take out the mobile armor's arms. The two simultaneously shoot the pieces but it deals no damage to Alvatore.
On board the Assault Container, Feldt Grace reports on the current status of the Gundams; Nadleeh is disabled, Kyrios is severely damaged and Exia and the GN Arms is in combat with Alvatore. Sergei Smirnov and Soma Peries begin their search for Kyrios. Inside its cockpit, Hallelujah is in control. Allelujah tell his other self that he "hasn't heard the world's call yet." Hallelujah agrees, takes off the helmet and pulls back their hair, planning on showing Soma "what a true Super Soldier" is made of. Kyrios then lights up and attack. Through use of precise thinking, Allelujah is able to strike both his opponents simultaneously, taking out Sergei's GN-X's left arm. He avoids all shots at him.
Alejandro/Alvatore unleashes a series of Fangs at the two pilots, managing to destroy Exia's shield, so Setsuna docks with Lasse Aeon/GN Arms. They take out the Fangs but Lasse is seemingly killed when his cockpit explodes. Setsuna strikes back and causes massive damage to the Alvatore.
Kyrios takes out Sergei's other arm and then surprises Soma. It a beam saber fight, Soma wonders out loud why Allelujah is able to outclass her, claiming to be the perfect Super Soldier. Hallelujah yells through the comm that reflexes combined with intelligence are what make the true Super Soldier and activates Trans Am and is about to kill her when Sergei takes the blow, allowing Peries to severely damage Kyrios. She then tends to the Colonel, not wanting to be alone anymore.
Setsuna tries to reach Lasse but then a beam attack comes from Alvatore. It is revealed that a golden winged mobile suit, GNMS-XCVII Alvaaron, was controlling the mobile armor. Alejandro Corner comments that he was outclassed by a machine equipped with the original Solar Furnace. He reveals to Setsuna that he intends to guide the world in a new age, one that Celestial Being won't be in. Alvaaron's wings charge up its beam rifle, unleashing a powerful particle beam at Exia. He assumes his enemy destroyed but Setsuna is able to avoid it with Trans Am. Getting the epiphany that he has finally found the world's distortion, he attacks the Alvaaron but its GN Field is impenetrable.
Flashing back to two years ago, Lockon Stratos explains to Setsuna as to why Exia is equipped with a solid sword: it's for counteracting GN Fields; within their plan, they also have anti-Gundam measures, so Setsuna is their trump card. In the present, he strikes the Alvaaron with Exia's sword. Using the Seven Swords system, Exia severely damages Alvaaron. Ribbons then contacts a bloodied Corner, revealing that he intends to guide the world in his place. He was only observing as to how far Corner could go with his schemes. Furious that Ribbons is usurping his family's long-laid out plans, Corner punches the screen, just as the mobile suit explodes.
Setsuna believes it is over, but is faced with the GN Flag, piloted by Graham Aker. He is extremely surprised to see the kid he met in Azadistan. The two begin a sword-saber fight, arguing about points-of-views of the world. Aker was just looking for his opportunity to avenge Howard and Daryl. The two suits are heavily damaged and seemingly destroyed each other in an explosion of GN Particles.
Marina Ismail soon receives an e-mail from Setsuna, asking why the world is so distorted. He promises that he will continue to fight for a new world with his Gundam. But by the time she reads his message, he'll be gone. Exia is last seen above Earth's orbit.
Four years later, Saji Crossroad sends a message to Louise Halevy and states he has achieved his dream of becoming a space engineer. Busy working on a the Union space colony, he finishes delivering some parts before gazing at the Earth. He and his colleagues spots a stream of GN particles. The colleague questions which nation it belongs to, Saji replies that the unit was not the United Nations, the color was different. "That light is a Gundam"
With the temporary disappearance of Celestial Being, the nations of the 328 countries, had merged. The Earth Sphere Federation was announcing at its 1st anniversary the dissolution of each nations' previous army and forming "one Federation peacekeeping army". The dream of a united world seems to have been achieved.
Elsewhere, Graham survived his encounter with Setsuna but is forced to wear a mask. Watching the Federation's press conference, Ali al-Saachez puts his drink down in frustration. Louise is seen riding an elevator with a man that looks similar to Tieria
At one of CB's L-point resource satellites, Wang Liu Mei, Hong Long, and Nena Trinity arrived to inspect the new Gundam units on board the Trinity mothership. Nena asks Wang if she likes the world as it is, and she replies that she has expectations that the world will change. Wang Liu Mei requests to view the very first Gundam to equip the GN Drive, The GN-000 0 Gundam. Ian Vashti complies and explains that the GN Drive was dismantled but was going to be reinstalled. The new unit, the GN-0000 00 Gundam, is commented by Wang as one that would change the world.