Romilly Kemp and her eccentric painter father have happy but sheltered lives in a ramshackle mansion in the English countryside. When her father finds fame with a series of children's books starring Romilly as the main character, everything changes: exotic foods appear on the table, her father appears on TV and strangers appear at their door, convinced the books will lead them to a precious prize.

But as time passes, Romilly's father becomes increasingly suspicious of the outside world until, before her eyes, he begins to disappear within himself. She returns to his illustrations, looking for a way to connect with her ailing father, and finds a series of clues he's left just for her. This treasure hunt doesn't lead her to gold or jewels, but something worth far more--a shocking secret that is crucial to understanding her family.

Written with tremendous heart and charisma, The Book of Hidden Wonders is an unforgettable story about growing up, facing mortality and discovering the hidden wonders that make us who we are.