It has been several centuries since the human race flew into space and abandoned Earth. What is left of the human race form a society named the Galactic Alliance of Humankind to ensure their survival against potential threats, namely a race of tentacled aliens known only as the Hideauze. Using advanced weapons and piloted robots or Machine Calibers, humanity fights to eliminate the Hideauze and find a new home. Ensign Ledo, a 16 year child soldier, has lived and breathed this military lifestyle, being more than willing to die for his people's cause. But when an assault on a Hideauze stronghold goes awry, Ledo and his Machine Caliber, Chamber, are flung into a wormhole and shot through space to unknown territory. They are discovered by another group of humans who speak an ancient dialect and rely on primitive technology to survive. Much to Ledo's shock, he discovers that he is no longer in space but on a ocean covered Earth which, according to the Galactic Alliance, has long been uninhabitable. What has happened to the earth after all these years, and will Ledo be able to get the answers he needs while fitting in with the natives?
The rest of the main cast are mainly there to teach Ledo about the new society on earth and help him grow. That isn't to say they aren't good or entertaining, with a few getting their own mini arcs as the episodes progress. However, with only 13 episodes to tell a complete story from start to finish, the focus isn't on them for very long. It makes sense from a production stand point, and while I personally consider the show is much stronger for it, the lack of development may bug viewers who look for strong side characters. There are several stand-outs characters such as Amy, Pinion, Bellows and Ridget being key among them but save a few other side characters, the rest seem to blend together.
Gargantia the Verdourous Planet is available on Blu-ray in both languages and is available to stream on Crunchyroll, Netflix [US/Canada], Hulu and Viz.com