This is a magical picture book following the latest adventure of Pipkin, the little penguin with big ideas. Pipkin the penguin is always asking questions like 'How Big is a Million?' and 'How High is the Sky?' Now, he has a new question: 'How Deep is the Sea?' A special fold-out poster at the end of the book shows Pipkin diving into the sea, showing what can be found at the different depths. it is gorgeously illustrated by Serena Riglietti.