Serena, Amy, Raye, Lita, and Mina all transform into Sailor Moon, Sailor Mercury, Sailor Mars, Sailor Jupiter, and Sailor Venus and head for Mugen School to stop Doctor Tomoe and Mistress 9 once and for all. Mistress 9 creates a barrier around the school, using all remaining Daimon pods to create several red, unnamed, Jell-like Daimons. The Sailor Scouts fight them, but not even the Moon Spiral Heart Attack is enough to defeat them all.
Using a shadowy hand, Mistress 9 reaches through a portal and pulls Sailor Moon into the school, to where she and Tomoe are. The Daimons all hide in the barrier until Sailor Uranus, Sailor Neptune, and Sailor Pluto arrive in a helicopter. The Daimons attack the helicopter and blow it up. At the last second, Sailor Pluto uses a forbidden technique to stop time. She then teleports Sailor Uranus and Sailor Neptune to the school, and resumes time. The helicopter explodes, killing Sailor Pluto.
Occasionally, Hotaru is able to take over Mistress 9's body and talk, before Mistress 9 regains control. The barrier gets bigger and stronger, so Sailor Mercury, Sailor Mars, Sailor Jupiter, and Sailor Venus use the Sailor Box (the attack they will later use in the future to defend Crystal Palace from the Negamoon Family) to contain the barrier.
Mistress 9 sends Doctor Tomoe to fight off Sailor Uranus and Sailor Neptune. He confronts them in a hallway full of several empty monsters of his creation. While talking to them, he reveals that he is actually a Daimon possessing Tomoe. The Daimon, Germatoid, leaves Tomoe's body and reveals his true form to them. Sailor Uranus uses World Shaking and blows him to bits. He enters the humanoid monsters, and fights Sailor Uranus and Sailor Neptune. They are immune to all of the two outer Sailor Scouts' attacks, and stretch their arms to wrap around them. Sailor Pluto's spirit tells them to use their Pure Heart treasures, and the Space Sword and Deep Aqua Mirror appear. Sailor Neptune uses the Deep Aqua Mirror to immobilize all the Germatoids, turning them all transparent and revealing the true Germatoid among his many clones. Sailor Uranus stabs him in the face with the Space Sword, destroying him and leaving only a destroyed Daimon pod. All the clones crumble to pieces.
Mistress 9 takes the form of Hotaru and pretends to be her when Sailor Moon arrives, however she mentions Serena's name (when Hotaru was unaware of Sailor Moon's true identity), revealing to Serena that she is Mistress 9 and not Hotaru.
- Sailor Pluto and Germatoid (the Daimon who was possessing Doctor Tomoe for the whole show) are killed in this episode. This marks Germatoid's final appearance, but Sailor Pluto's spirit appears two episodes later