Captain Kobayashi announces that Sidonia will set course for the Lem Star System, pursuing the Gauna's mothership who threatens the colonists at planet Lem VII. Just when Guimera Tsumugi is about to sort for a joint exercise, she detects a large Gaun... (more)a formation approaching Sidonia. At the advise of Kunato and direct orders from the captain she departs to attack it alone. However, the Gauna create a massive structure to trap her. A platoon of Guardian Pilots sortie to rescue the Guider from the Gauna.