Join the Winx Club, a group of fairies who fight evil using their unique magical powers! In this volume Icy overhears one of her professors talk about a powerful, forbidden book. Wanting its power, the Trix decide to use someone who is experiencing emotional pain to unlock the book- Stella. But once the book is unlocked, the power they sought was more than they had bargained for.

Then Musa's feelings for Riven have bled into her dreams -- and her conflicting feelings for Mitril, a young interdimensional adventurer who wishes to win her heart, are not making things better. At the same time, Bloom learns of Madame Greta's personal tragedy being the reason for her crabby and jaded personality. To give Greta some closure, Bloom decides to take matters into her own magical hands. Lastly, As a sign of gratitude for helping her reconcile with her mother, Stella gives Bloom a magical diary. Bloom is grateful for Stella's gift but she is facing her own set of problems, as she is having trouble keeping up with everyday expenses. Musa also shares the same problem and the two go job hunting. Musa ends up working for the school's librarian while Bloom competes for a job opening at a cafe called the White Horse.