The Dream Witch haunts the forest beyond the kingdom of Bellumen, waiting to collect on a horrible debt owed by the king and queen -- the heart of their only daughter, Princess Olivia. Until she has it, none of the kingdom's children are safe.
As Olivia's thirteenth birthday approaches and the witch's deadline draws near, her desperate mother seeks help from Prince Leo of neighbouring Pretonia. But the treacherous prince seizes their castle instead, determined to marry Olivia and take over the kingdom.
So Olivia makes a daring escape from the castle, two friends by her side: the peasant boy Milo and a curious talking mouse with a surprising past. Together, the friends face certain danger and fantastical adversaries to save their families and rescue a kingdom.