Gargantia on the Verdurous Planet : Season 1

Humans have left Earth and have made a paradise in space, Avalon, as humanity's new home and created the Galactic Alliance of Humanity to expand their journey through it. A threat known as Hideauze appeared before the Alliance and a war rages between them. Second Lieutenant Ledo and his A.I. Robot Partner Chamber joins the latest attack against the Hideauze. The attack ultimately ends in failure and a retreat order is issued, but Ledo is unable to return and is cast out into space. 6 months

Deciding to try and open a dialogue with these people, Ledo stays pinned to the pylon. They ask to talk to the Alliance in charge, but the crew have no idea what he is talking about and they believe that Chamber, who is translating, has another person inside. As Ridget, the commander, and the crew try to decide what to do, Amy gives Red food and begins talking. She explains that this is Earth, and when it was frozen over, some humans escaped to the stars while others stayed. Eventually, the ice

After Chamber wiped out all of the pirates that were threatening Bellows and her people, Ledo is perceived as a menace and kept under guard by the crew of the Gargantia. And perhaps rightfully so, as the pirate armada that is Empress Lukkage's fleet is racing towards the Gargantia Fleet with bloody revenge in mind...

In order to compensate for the damage to the hangar they caused, Chamber is put to work hauling around heavy cargo, but that leaves Ledo on the sidelines with nothing to do. Amy takes him around the fleet and introduces Ledo to the knowledgeable Dr. Oldham as well as her sickly but wise younger brother, Bebel.

Amy tries to help Ledo find a job and introduces him to a number of different industries aboard Gargantia, but he's just not able to land one. Then the wind dies down and the waves cease, making it a "Calm Day", during which time the fleet shuts down so a lot of repair work can be done. But for non-repair-related personnel, it's time to take a breather. Pinion invites Ledo, Amy and her friends to a BBQ party. Everything seems to be going smoothly...

Ledo decides to work as a fisherman, but he finds himself unable to pilot a regular Yunboro and sends Chamber to assist the other fishermen instead. Pinion then invites Ledo for lunch and offers him a position at his crew, but Bellows appears and also offers him a job at her salvage team. In the occasion, Amy and her friends dance to the crowd and Ledo mistakes a cooked octopus for a Hideauze and is about to shoot it until the others assure him that it is not an enemy, but food instead. Chamber,

When Ledo has an encounter with a whalesquid undersea, he attacks and kills it because of its similar appearance to the Hideauze. Little did he know that whalesquid are considered sacred, so murdering one is taboo, and soon the whole ship is in an uproar over it. Ledo, however, believes that whalesquid are Hideauze and he's determined to carry out his mission by slaughtering more of them before they decide to target humans on Earth. Just as Amy tries to stop Ledo, a huge pod of whalesquid

On his deathbed, Fleet Commander Fairlock entrusts Ridget with Gargantia. Meanwhile, Chamber finally gets a fix on the location of the Galactic Alliance, but they're so far away that Ledo will never be able to get home. As preparations are underway for Fairlock's funeral, Shipmaster Flange announces that he's leaving Gargantia. Ridget struggles to keep other Shipmasters from following suit. Pinion has plans of pillaging the ocean floor, so he joins the like-minded Flange. Amy is sad when two

Ledo and Chamber go deep sea-diving to exterminate Earth's Hideauze.

With all the Hideauze in the area killed, Pinion and his crew manage to salvage ancient technology not seen anywhere, but instead of sharing it with the rest of mankind as originally planned, Pinion claims that they have the right to keep it to themselves, and sends a message to the other fleets warning them to keep out of their territory. As the message reaches the Gargantia, the fleet had just reorganized itself and there is the concern that other ships may leave to join Pinion's side as well.

Kugel contacts Ledo and instructs him to return to his side. Upon reuniting with him, Ledo learns that Kugel is struck with some disease that does not allow him to leave his cockpit. When Ledo tells him what he learned about the Hideauze, Kugel reveals that he always knew about it, just like the high command of the Gallactic Alliance, and despite that, he insists to fight them, and was all this time organizing a powerful fleet with a militaristic society with that purpose, whose intention is to

Kugel's fleet prepares itself to attack the Gargantia. Ledo tries to dissuade Kugel with no success while Pinion is approached by Lukkage who plans a rebellion at the fleet. Confused about what he should do, Ledo witness the people of the fleet throwing their sick and weak on the water and fearing that the same will be done to Bebel, he decides to confront Kugel by himself. Agreeing with Ledo's decision, Pinion equips Chamber with some extra weapons, while Lukkage and Flange make preparations

Striker claims that it was following Kugel's instructions after his death and eventually reached the conclusion that to ensure stability to the fleet, it was necessary for the humans to view it as their god. Both Ledo and Chamber reject Striker's offer to join its side and decide to destroy it. Unable to defeat Striker in their current condition, Ledo decides to merge his nerve system with Chamber's interface to increase its capabilites at the cost of his life, but Amy appears soon after to tell