Stratos 4 Advance

Mikaze, Ayamo, Karin, and Shizuha were sent off to become official Comet Blasters, but have returned due to failing exams. Their past instructor, Sayaka, appoints them to be instructors since three new recruits will be training! Kiriko, Mirei, and Mana are the new interns, each with their own level of skill in operations; however, the world is inevitably invaded by aliens, and the three girls must put aside their teachings to battle these enemies. As they experience some struggle while in combat, they begin to think: perhaps there are enemies coming from the inside?