The episode begins in the past, shortly after the fourth defensive war. Doctor Yure manages to integrate photosynthesizing with the remaining humans and restores Sidonia's population. In the present Nagate and Izana go to observe the Gauna placenta that has taken the form of Shizuka. They both meet Numi Tahiro, a scientist at EBD, who wants to use Nagate in a series of tests to see how the Shizuka/Gauna hybrid would react in his presence. Nagate tries to communicate with the Gauna by mentioning Shizuka's name but it reacts violently seemingly trying to attack Nagate. Meanwhile, Kunato has relieved himself from piloting as the events during the previous battle had caused psychological distress. He then witnesses Captain Kobayashi, Dr Yure and Ochiai's clone enter an unknown area. The Captain removes unknown details from a site known as the auxiliary brain using the Ochiai clone, as only Ochiai's mind can enter the database, the clone is then put to sleep by the Captain's orders but she is unaware that Kunato was watching the events through security cameras. As time passes both Izana and Yuhata display affection towards Nagate, but Nagate spends more time with the Shizuka/Gauna hybrid as it becomes less and less hostile as Nagate consistently communicates with it. Nagate is also promoted to squad leader and leads his squad on several successful battles with the Gauna, after many battles Nagate agrees to go on a vacation with Izana to take a break. Numi Tahiro analyses what the Shizuka/Gauna hybrid is staring at, as whenever Nagate is not present the hybrid would constantly stare at one point in a wall within its confined space. It is then revealed that the hybrid is actually staring at where the kabizashis are stored, far off in another part of Sidonia, seemingly scared. In the distance Benisuzume stares intently at Sidonia and at the kabizashis storage sight.