Hoping to bring back her father and the other missing royals of Cello, Princess Ko gathers a group of teens, each with a special ability, including Elliot, whose forbidden communications with Madeleine may be the key to traveling across worlds.

Fourteen-year-old Madeleine of Cambridge, England, struggling to cope with poverty and her mother's illness, and fifteen-year-old Elliot of the Kingdom of Cello in a parallel world where colors are villainous and his father is missing, begin exchanging notes through a crack between their worlds and find they can be of great help to each other.