Sousei Kitan Aerial is based on a giant robot anime game. The anime show follows ,to the letter, the game storyline. Like most robot anime shows, Sousei Kitan Aerial is post apocalyptic. The year is 2040. Global warming has finally melted all the polar ice caps. The entire earth lies underwater. Like Noa's arc, humanity now lives in Aquapolice City. This floating city is the home of the only remaining 100,000 humans. After 9 year, supplies are running low. There is also lot of overcrowding. To make matters worse, this city has been attacked by robotic beings called SPOOK.
To defend themselves, the humans created their own robots. This is where Tougon Shin comes in. He is the main character of the story. In school, he meets a robot chick Hoshiumi Nagi. Within her lies, the ultimate weapon to defeat the SPOOKs. Like most robot chicks, Nagi acts like Eureka. She is a bit dense around the edges.
She is going to school to assimilate with the humanity. When the war with the SPOOKs recommenced, Nagi acts as OS for the army. She leads them in battle against the SPOOKS. On the side, she develops a relationship with Shin. As time passes, she falls in love with Shin. I think that is everything worth mentioning about Sousei Kitan Aerial. The robot fights are pretty cool. For this reason, Phi Star gives Sousei Kitan Aerial 5 stars rating.