The year is AD 2225 and mankind has spread from Earth to inhabit nearly all the planets or nearby moons in colonies and settlements. Space travel has become popular and most people decide to become astroauts as they grow up. Schools set up to train future space voyagers have been created virtually everywhere, one of the most famous being the Liebe Delta, positioned somewhere in Earth's orbit. This is the setting in which the show Infinite Ryvius takes place.
As for the story, the plot is so complex it would take too long to actually explain everything that happens on the show. Besides, I don't want to spoil everything. The story begins when the Liebe Delta is under attack by terrorists and all the adult instructors, the staff and a few others were killed. Now, the Liebe Delta space station, inhabited only by kids or teenagers, is about to crash-land in into the depths of the Geduld Sea. Suddenly the mysterious ship named Ryvius, hidden somewhere aboard the Liebe Delta, activates itself and all the survivers manage to escape. However, they are still stranded in space and have no way of returning to Earth. This is where the actual story begins.
From here and until the very end, the survivers must learn how to co-exist in peace, which is not always easy. Infinite Ryvius has tons of characters, both main and secundary, all of which have at least one line on the show. Each character has a unique personality and his own beliefs. Tension usually arrise between them, no matter if they used to be friends or even brothers. Of course, the show does a superb job with character development, and by the end of the series you'll be surpirsed how much some of the characters have actually changed (both for the better and for the worse).
The highlights of the series have to be the confrontations between different characters, but especially between the two main characters of the show, the Aiba brothers. These scenes are so intense you'll never know what the outcome of their confrontation will be.
Overall a great, enjoyable series with a lot of character development. An abmitious project, which has definetally paid off. A very dynamic show, which will keep you on the edge of your seat throught its entire run.