Ellie, ten and a half years old, is entering sixth grade in Saumur. Shy and passionate about nature, she spends her time immersed in books, particularly about ornithology. She intrigues Anna, the college librarian, a mysterious woman with whom she forms a relationship full of mischief. The day Ellie absolutely has to return a book to him, the door to the library is closed. Ellie then decides to take it directly to Anna, who lives on an island on the Loire, a few kilometers from the school. An island full of birds.