Terra and Aevum have been living in peace since they stopped the threat from destroying everything. Terra has learned to create new spirits and creatures to help her take care of the Earth. The seasonal spirits of spring, summer, autumn, and winter help their mother, Terra, bring the seasons to the world. Flare, the newest summer spirit, has just been born and is learning about her new life. However; questions arise when she is told that humans can't seen them and that her winter sister is "sick".