Ami Mizuno is the top student at her School — quiet, brilliant, and almost painfully shy. She spends most of her time alone with a book, more comfortable with numbers than people. But underneath the reserved exterior is the Guardian of Wisdom and Water, Sailor Mercury, whose calm mind and cool resolve make her the team's strategist. It takes a certain kind of person to draw her out of her shell — and Usagi Tsukino is exactly that kind of person.