Summary for the movie
When the Evil Madame Vadiane kidnaps Chibi-Usa, the senshi rush to her rescue with the aid of Chibi-Usa's new friend, Peruru. After trying to find Chibi-Usa and fight off Vadiane's henchmen to no avail, the three outer senshi (Neptune, Uranus, and Pluto) come to their aid. To rescue Chibi-Usa before she falls into a permanent dream filled sleep, Usagi must enter the Black Dream hole and save her. With some luck and a lot of effort, Sailor Moon saves Chibi-Usa, and she transforms to help Usagi.