Usagi is furious when Mamoru forgets her 15th birthday. When Mamoru buys her an expensive pair of glass slippers to make up for it, he fails to realize that Kaolinite sabotaged the shoes with a Daimon egg to steal her pure heart crystal. To make matters worse, Kaolinite steals Usagi's Cosmic Heart Compact leaving her unable to transform, and Tuxedo Mask gets captured.