A clever and playful celebration of the things we can hear, can't see, but can imagine! ' Listen. Can you hear the susurrus?' said Grandma. 'What's a susurrus?' asked Frankie . Frankie doesn't know what a susurrus is. She knows it not it's not a platypus, an octopus, or even a kind of saurus . So Frankie searches for the susurrus, while her friend Andy has suggestions as to what a susurrus might be. Everyone has a go at guessing what a susurrus is. But no one has ever seen one. What is a susurrus? Frankie now knows. Do you?