Mamoru and the girls receive an invitation to a party hosted by Edwards, an Englishman who lives alone on the outskirts of the town.
Saphir learns of Wiseman's true intentions and tries to warn his brother, only to be attacked by Wiseman himself. Barely managing to escape, Saphir is surprised when he is saved by Petz and her sisters.
Chibi-Usa finally decides to return to the future to save her mother. With support from the Sailor Guardians and Tuxedo Mask, she overcomes her fears and opens the Door of Space and Time.
After being out sick a couple of days, Chibi-Usa returns to school eager to see her friends. But to her surprise, her friends and teachers begin attacking her.
Artemis is out to prove he is capable after being teased by Luna. While on patrol, he encounters a suspicious-looking man who is gathering stray animals.
Usagi is still depressed over Mamoru calling off their relationship. Ami and Mako try to cheer her up by taking Usagi to a promise ring workshop.
The Black Moon clan sends down its next operative, Esmeraude, to open the Dark Gate in 20th century Tokyo.
Chibi-Usa falls into a coma after coming down with a mysterious fever. Usagi and the others are at a loss for what to do, when a Sailor Guardian calling herself Sailor Pluto suddenly appears before them.
Ami enters the World Chess Tournament, which is being held at the newly constructed Chess Tower. But Bertheir is also there, forcing Ami to transform and reveal her identity as a Sailor Guardian to the enemy.
Wiseman predicts that Chibi-Usa will appear at Hikawa Shrine. Learning of this, Rubeus orders Koan to go down there and eliminate their target.
Mamoru has a dream in which a mysterious voice warns him that being with Usagi will bring her great misfortune. Meanwhile, Sailor Moon is put into a deep coma after being attacked by a Droid.
Chibi-Usa leaves the house after being scolded by Usagi. Roaming the streets alone, Chibi-Usa is overcome with sadness and begins to cry, which draws the attention of Rubeus and the Four Spectre Sisters.
The girls enjoy some vacation time on an island. But during lunch Chibi-Usa and Rei get into a small fight, causing an angry Chibi-Usa to go out to the sea alone.
Minako and Makoto clash over their opposing views on love. Wanting to break the tension, Usagi takes the girls to check out a new accessory shop, unaware that Petz and Calaveras run the place.
Rei's grandfather is upset over the fact that Hikawa Shrine has had fewer female visitors lately. He then decides to retire as head priest to start a new business, which would allow him to be around young women, much to Rei's annoyance.
Usagi, Mako, and Ami see a boy being attacked by one of Ail and An's Cardian monsters. To Mako's surprise, the boy turns out to be her childhood friend Shinozaki.
Two months have passed since the Sailor Guardians defeated the Dark Kingdom. Having lost all memory of being Sailor Moon, Usagi now lives her life as an ordinary girl.
Sailor Moon confronts Queen Beryl's Endymion. She attempts to free Endymion from Queen Beryl's control, but his brainwashing cannot be undone. With the fate of the world hanging in the balance, Sailor Moon is forced to fight the man she loves.
The Sailor Guardians head out into the Arctic Circle. Having anticipated their arrival, Queen Beryl sends the DD Girls, who ambush them. To Sailor Moon's horror, the Sailor Guardians fall one after another as they try to defeat the DD Girls.
Sailor Venus finds the Dark Kingdom's hideout. The Sailor Guardians fall into Kunzite's trap, which hurls them into the past. The girls find themselves in a world called Silver Millennium, where they meet Queen Serenity, the mother from Usagi's past life.