Lulu, who loves every sort of animal, tries to convince her teacher that their class guinea pig needs a companion. Unfortunately, her methods lead Mrs. Holiday to announce that if anyone brings another animal to school, she’ll trade their class pet for a stick insect. When their weekly visit to a nearby park ends in disaster (large dogs running wild and destroying ducks’ nests and eggs), Lulu catches the one remaining egg as it rolls downhill, and she pockets it. All through the school day, she protects the egg and keeps it warm, revealing her secret only to her best friend (and cousin), Mellie. When the egg begins to hatch, though, Lulu finds a powerful, if unexpected, ally.