Mihiko is one of several officers who accompany Kaori Koyamada down in a submersible to monitor a Kaiju emergence in real-time. Mihiko and the crew spent days underwater, tracking the Kaiju and she begins to doubt Kaori’s belief that Thunderhead will any appear any time soon.
Mihiko is proven wrong when she, Kaori and the crew hear Thunderhead’s approach. When the submersible crosses paths with Thunderhead, it’s caught in its grip. The crew attempts to abandon ship, Mihiko tries to Kaori to leave with them, pleading with her to abandon the data analysis and save herself. Kaori refuses, and as the submersible is further attacked, Mihiko and the crew are rendered unconscious.