Icy, Darcy and Stormy are sent to the Omega Dimension as exiles. There, Icy manages to free herself and her sisters. However, during a battle against the snakes, protectors of the Omega Dimension, Icy meets and frees Valtor, an evil wizard who helps the Trix escape.

Valtor quickly gets much more powerful and terrifies Andros, Solaria and other magic worlds in order to become the most powerful wizard in the entire Magic Dimension.
The Winx begin their third year at Alfea. There, they get to know a powerful and evil wizard named Valtor, who is trying to take over Magix and destroy the Winx with Trix's help.

In the meanwhile, the six fairies have to go through several struggles and battles to finally earn their new transformation: Enchantix.

The Enchantix is a fairy's final transformation and the hardest to obtain. It's the door that opens up to stronger powers and transformations; it requires a sacrifice and a great desire and will to save someone from a fairy's own kingdom.
How will Bloom archieve Enchantix, if her kingdom is destroyed?