Daniel wants to be a detective and is convinced he has all of the qualities to be a great one. He even has his first case: to discover who ate the cheese sandwich his dad had prepared for him for breakfast. Daniel starts to follow the clues and jots them down in his notebook and tries to solve the case. "Daniel quiere ser detective y esta convencido de que tiene lo que necesita para convertirse en uno muy bueno. Incluso tiene su primer caso: descubrir quien se ha comido el bocadillo de queso que le dejo preparado su padre para el desayuno."" Daniel sigue todas las pistas y las anota en su cuaderno y intenta dejar el caso cerrado."

Marta Jarque is an author of children's books, including Bet pierde la banda. Daniel Jiménez is an illustrator of children's books, including El cangrejo ermitaño and Daniel tiene un caso.