Mikazuki's group, Tekkadan, has been commissioned to escort Kudelia on an inspection of a halfmetal mine, but suddenly, finds itself under attack by space pirates.
Despite some casualties, Tekkadan has successfully repulsed the space pirates of the Dawn Horizon Corps. It appears, however, that this enemy was just one part of a huge space pirate group.
Deploying all the fighting strength it possibly can, Tekkadan attempts to capture Sandoval Reuters, the leader of the Dawn Horizon Corps, with help from Gjallarhorn's outer lunar orbit joint fleet, Arianrhod.
Mikazuki and Orga visit Allium, leader of the ideological group Terra Liberionis, to resolve the issues surrounding the attacks of the Dawn Horizon Corps.
Tekkadan's Earth branch, which is now serving as a military advisor to Arbrau, is consumed with preparing the launch ceremony for the Arbrau Defense Forces. At Makanai's request, Tekkadan takes charge of security for the ceremony venue.
A conflict between the rival economic blocs Arbrau and SAU breaks out as their armies clash on the Balfour Plain.
Gjallarhorn has received a mediation request from the SAU. In order to break the prolonged stalemate, McGillis personally enters the battlefield in a mobile suit.
The fighting ends as the rival economic blocs SAU and Arbrau agree to peace negotiations. As they remember their fallen comrades, the members of Tekkadan decide to withdraw from Earth.
After many complications, Tekkadan finally joins the battle against the Arianrhod fleet.
Tekkadan revives and launches an attack, aiming to escape the battlefield. Meanwhile, the fight between McGillis and Gaelio becomes increasingly ferocious.
Tekkadan plans to return to its Martian headquarters and start over. The situation, however, has undergone a dramatic reversal.
Tekkadan is in a difficult predicament. A huge Gjallarhorn force then begins deploying around its Martian headquarters.
Gjallarhorn intends to launch a mopping up operation against Tekkadan as the hour of its commencement is drawing steadily closer.
Gjallarhorn begins its Tekkadan mopping up operation, with Tekkadan's future in question.