Nightmare Tree

In this tale set in the gorgeous Seychelles Islands, Jonah Comfait refuses to believe his father has drowned at sea and sets out in a sailboat to search for him. His search carries him out of his everyday life to the hidden, magical land of Mysterion. There, in order to free his father, Jonah must defeat the djinn, who enslave people and feast on their dreams, and save Mysterion.

The first Tale of Mysterion. See also the second installment, The Edge of Mysterion