Rubeus has captured all the Sailor Scouts except Sailor Moon, whom he tells to give him Rini and the Imperium Silver Crystal if she wants to see them again, giving her a few hours to decide, before he returns to learn of her decision. With that, he returns to his ship, and it retreats back into the clouds.
After trying to make a decision, Sailor Moon goes to face Rubeus. Though she does not intend to give Rini over, Rini follows her, and Rubeus takes them both inside his spaceship, which goes into space. With the other Sailor Scouts trapped, Sailor Moon has to face Rubeus alone. Sailor Moon attacks Rubeus with Moon Scepter Elimination, but he counters with a dark energy wave. He then activates the gravity on his ship, turning it up to force Sailor Moon to the ground. He then reverses it, sending Sailor Moon flying to the top of the room. Rini notices that Rubeus' source of power is a crystal in the middle of the room.
Rubeus turns on the gravity again, to maximum capacity, but Sailor Moon is able to stand up, despite the G-forces pressing on her body. Rubeus turns off the gravity manipulator, then enters a beam struggle with Sailor Moon. While Rini attempts to break the crystal that raises Rubeus's power, Rubeus overpowers Sailor Moon and prepares to attack Rini, but Sailor Moon attacks him with Moon Scepter Elimination again, forcing him to focus on her again and allowing Rini to eventually break the crystal, causing Rubeus to lose all his power, and releasing Sailor Mercury, Sailor Mars, Sailor Jupiter, and Sailor Venus.
Having lost his bargaining chip with the Scouts as his hostages, Rubeus programs his ship to self-destruct in a suicidal move to take the Scouts with him, starting a fire in the room. The Scouts panic on how to escape. When Sailor Mercury suggest teleportation, Mars fears that because Sailor Moon used up all her power, they will never get home but is reminded if they use all the power they have left, they will surely make it home. The Sailor Scouts successfully teleport back to Earth with Rini. Emerald appears, and Rubeus asks her to take him back to the future, but instead she tells him that he struck out, and returns to the future without him, leaving him screaming her name to no avail before the ship explodes, killing Rubeus, once and for all.
In the future, Emerald informs Prince Diamond of Rubeus' failure. He looks at a hologram of Neo Queen Serenity, as he is in love with her.
- Last appearance of Rubeus
- First appearance of Prince Diamond
- A scene where Emerald talks to Rubeus before his death edits where Emerald smacks Rubeus' hand with her fan. This would explain why Rubeus is holding his hand afterwards.
- From this episode onward, Sailor Moon says "Moon Scepter Activation" instead of "Moon Scepter Elimination".
- This episode is similar to the Monster Rancher episode End of Durahan, as both titles give that the significant villain is going to die in this episode. Also, the villain loses a beam struggle to a protagonist and confront a female villain while the heroes teleport off the ship, and the ship that he is inside is destroyed.