After getting in some trouble, Akira gets approached by an enigmatic recruiter who tells him about the expendable foot soldiers known as Yakitori.

Ten months ago, Tyrone Baxter, Erland Martonen, Amalia Schulz, Zihan Yang and Akira Ihotsu meet for the first time on Earth before launching to Mars.

The K321 unit heads into enemy territory to carry out their "harassment" mission while 10 months ago, back in the Kitchen, their training begins.

Back in the Kitchen, the K321 learn that their teamwork is lacking, and they find out that they're being trained differently from everyone else.

After their brutal counter-attack against the enemy, the K321 unit are left to put together their own escape plan. Akira has a risky idea.