When a 13-year-old Maria’ father dies and leaves her as a homeless orphan, she has to leave London and move to Sir Benjamin, her eccentric uncle she never heard about before, to his mysterious estate called “Moon Valley”. Maria finds herself in a world divided with an ancient fight with the Dark Lord de Noir. She is the last Moon Princess and she has to overcome a family pride and disclose the mysteries of the past before the Moon rises for the 5000th time and the sea will take up the Moon Valley.