In the school library, Zoe found a book with no title on the cover. It was dusty and hidden behind other books. She opened it and saw strange symbols and drawings. Curious, she borrowed it and showed it to her friend Max. They tried to decode the symbols and discovered they were part of a puzzle. Each page had clues that led to the next. The final page said, 'Look under the old oak tree.' After school, they ran to the tree in the playground and found a small box buried beneath the roots. Inside was a note: 'Well done, readers. You solved the mystery.' Zoe and Max laughed and high-fived. They returned the book and told the librarian, who smiled and said, 'That book has been waiting for clever minds like yours.'