Emily and Alexander travel to visit their cousin Fumi in Japan to participate in the 7-5-3 festival, where Japanese children are allowed to wear adult clothes. Fumi lives with Kiko, the daughter of a silk painter who was robbed by rats shortly before Emily and Alexander arrived. Unfortunately, the Japanese emperor wants the kimono for Princess Mitsumi from im, of all people, but all the designs Kiko's father delivers displease him.