The day after 11 year old Kitty and her family move into a new house, she explores the backyard and suddenly shrinks to the size of a bug. She finds a city of small people living in her backyard. Among them are Paradox, Meriel and Jendy, three friends who let Kitty into their group, "The Three." Kitty would like to get home, but there are important things to be done. Paradox's sister, Delight, has been kidnapped by the mysterious Shadowslayers, and Paradox is determined to get her back. The four girls embark on a perilous journey to the Shadowslayers' city to save Delight... and the entire backyard. But that's not all they will have to deal with: Jendy is stuck in an enchanted sleep; Paradox can't stop thinking about Jake; and Kitty's dad has invited some friends to her house, where they're sure to find out her secret. Luckily, Kitty and the rest of The Three have their friends to rely on, even if some of those friends are boys, one inch tall, made out of sand, or all of the above!