The Moore Brotherhood's Beehive flagship launches a squadron of GMs across the Thunderbolt Sector to break through the Principality of Zeon's defenses, only to be shot down by the Living Dead Division and their Big Gun units. Io Fleming, who manages to eject from his GM, guns down a Rick Dom pilot before commandeering the mobile suit and returning to the Beehive with the sniper location data. He is then assigned to pilot the new Full Armor Gundam prototype, which he uses to flush out three Big Gun units. Living Dead Division ace sniper Daryl Lorenz vows to avenge his fallen comrades and kill Io.