Luna types away on a computer. Information such as age, birthday, blood type, and school pop up next to pictures of Usagi, Ami, and Rei. Next to Mamoru's picture, there are many unknowns. "Friend or enemy???" Luna types. "A suspicous character!"
The next morning, Sailor Moon is on the front page of Ikuko's newspaper, along with a story on Princess D's arrival in Japan with her mystical treasure. Usagi runs past, late for school again. She fills the reader in on everything that's happened so far.
At Juuban JHS, the girls are excited about Princess D and the big party in her honor planned for that night. Of course, Usagi wants to go to the embassy party.
At the game center, the three Senshi hold their meeting. Rei wants to know just why she has to be a soldier and where Luna came from. Luna says that she cannot tell them everything yet, but that their purpose is "to protect the Princess." Luna doesn't know who the Princess is because she's been sealed; this seal will protect her and the Ginzuishou until the Senshi can find her.
Motoki interrupts the meeting to talk about Princess D. Umino also joins them, showing the girls a poster of the Princess. She wears large glasses, just like Umino. This just makes Usagi want to go to the party even more, but Rei has a funny feeling about the whole thing.
The dark-haired general looks at Jadeite's decaying corpse in its glass coffin. He declares himself to be Nephrite and claims he will get the Ginzuishou. Queen Beryl likes the sound of this, since the crystal will restore the Dark Kingdom to power.
Back at home, Usagi learns that her father is going to the embassy party to cover it for his magazine. She can't take it anymore, and takes out her disguising pen. "Moon Power! Transform me into a princess!" She appears in a beautiful, low-cut white dress.
The embassy party turns out to be a masked ball. Usagi is enchanted, but Rei and Ami are all business-minded. They split up to look for Princess D, thinking she might be their Princess, and her treasure may be the Ginzuishiou. Usagi is too wrapped up in the party to do anything else.
Suddenly, a woman spills some of her wine on Usagi's dress. Usagi runs from the ballroom, looking for a bathroom to wash away the stain. As she runs, she drops her handkerchief, which is embroidered with "Grade 8, Class 1. Tsukino Usagi." A masked man in a tuxedo picks it up.
Soon, Usagi is hoplessly lost and alone. Before she can begin to panic, the masked man walks up to her. "Beautiful princess, be my partner for a song." It's Tuxedo Kamen! He takes her in his arms and they begin to dance.
"I was just thinking that I wanted to see you," Usagi says.
"So was I."
They dance until Luna appears. Tuxedo Kamen vanishes before Usagi can see which way he went. To herself, she notes how warm her body feels from being with him.
Princess D is talking to her interpreter. She comments how she's second-best next to the treasure. The interpreter agrees and turns into a youma. The youma becomes a gaseous vapor and enters the Princess' body. Now possessed, Princess D steals the treasure and runs. Usagi sees the whole think and tries to stop her, but the Princess shoves her off the balcony.
Just in time, Tuxedo Kamen grabs Usagi's hand. "Usagi-chan! The pen!" Luna yells. Usagi takes out the pen and it extends, becoming an umbrella. Gently, Usagi and Tuxedo Kamen float to the ground.
"Today I was saved by you," says Tuxedo Kamen as he runs off.
Usagi turns into Sailor Moon, but her tiara doesn't appear. "Oh, no! It burned up with that guy! [Jadeite]!" Her body becomes warm, just like it was when she was dancing with Tuxedo Kamen. A new tiara forms on her forehead.
Nephrite's shadow leaves Princess D and appears in front of the three Senshi. Sailor Mars tries "Evil spirits, begone!" but it doesn't work. Tuxedo Kamen reappears to give some advice:
"To extinguish the darkness, you must have a powerful light."
Sailor Moon reflects the moonlight in her new tiara: "Moon twilight flash!" The shadow melts away.
The Princess is returned to normal. Her glasses have fallen off, revealing a very pretty face. The girls all wonder if that's how Umino looks behind his glasses. As it turns out, Princess D is not their princess and the treasure is not the Ginzuishou.
Before she has to leave, Sailor Moon picks up some "juice" [it's actually wine] and drinks it. She immediately gets sleepy and falls asleep in Tuxedo Kamen's arms. He carries her out to the balcony and kisses her on the lips. Luna catches him and chases him away.
"Are you our enemy? Are you our ally?" she demands.
"Well, if we seek the same thing... perhaps I'm your enemy."
A tall girls runs under the lightning-studded sky. "The coming of a storm," she murmurs.