Mariko Rosebank, codename “Rose Marie,” leads the all-female anti-terrorism force CAT. Her elite team is assigned to secure a secret international summit in the Alps… but Mariko suspects the terrorists may be one step ahead.

The third movie in the OVA series is a sequel to episode 18, which has new enemies (Cy Quo Adder and Plater Quiz) and new Heavy Metal mechas.

In the 24th century, on the war-torn planet Maris the conniving Queen Adama abducts Apple, a member of an heroic trio known as the White Knights, and imprisons her in the infamous Zone. Even though no one has ever returned alive from the Zone — and despite the low ammo at their disposal — the other knights follow their companion. What they find there, however, is an enigmatic figure with a mind-bending revelation...

Set in the final years of Japan's shogunate, all characters from the main series, Silent Mobius, appear with the same name. According to the setting, they are said to be the previous lives of the characters in the main story...

The remaining forces of the Solnoid and the Paranoid races now head toward Sigma Narse, a forgotten star system with a dying red giant for their final confrontation. The crew of five Solnoids who survived the battle at the ninth star system are sent to meet Capt. Nebulart, head of Intelligence, for what appears to be the last hope for both races.

The war between Solnoids and Paranoids continues, but the conflict reaches a new height as both races complete their Planet Destroyers. This new technology wipes out several star systems leaving only the ninth star system undamaged. As both races head towards it, a Solnoid ship finds Lufy, an attacker cryogenically preserved inside an assault trooper among space debris. Reawakened, Lufy is invited to join a group of Solnoids who are set to complete the original secret mission of her former crew.