A small boy named Ember lives in a city of giants. Always feeling the odd one out, Ember's life changes when he meets the giant sea turtle Lua, who takes him to a mysterious island with a school for little creatures. Ember tries to make new friends with some of his new, bizarre, alien- and animal-like classmates, but some are not interested in making friends with the weird new boy at all. Struggling to adapt yet again to his new world, Ember lands in the middle of a mystery, with a monster from the otherworldly deep threatening everything in his world.