The Winx realize their quest is not yet over and in order to obtain Sirenix, they must find the Source of Sirenix, and to do that, they must look within themselves and use everything they learned. Meanwhile, Tritannus steals Daphne's Sirenix powers and gives them to the Trix.
- Anti-Climax: The Winx have obtained the three gems of self-confidence, empathy and courage, but the Sirenix Quest is not yet over; to complete the quest, they must find the Source of Sirenix, which can only be found if they "look within themselves".
- Art Shift: When the Winx are in the Infinite Ocean, everything is in CGI.
- Big "NO!": By Daphne as Tritannus steals her Sirenix.
- But Now I Must Go: The Sirenix Book vanishes upon explaining that the gems were collected but the Source of Sirenix still has to be found. The Winx were not too happy at this, especially Stella.
- Celestial Deadline: It turns out The Sirenix Quest was not yet over; the Winx have until sunset to find the Source of Sirenix, since that’s when the lunar cycle ends and they’ll lose their powers forever.
- "Eureka!" Moment: Bloom has one, realizing the Sirenix Book’s riddle as she contacts her Guardian, telling her finding the gems is not the end and they must embrace their qualities to find the source. The Guardian congratulates them and tells her to go to the place where the quest began, making her realize Lake Roccaluce is where the Source of Sirenix can be activated.
- Evolving Credits: The theme song changes vastly as of this episode to reflect the Sirenix transformation. Averted for the ending theme, however.
- Friend-or-Idol Decision: Bloom is stuck between two decisions: Either save Lake Roccaluce from drying up or tell Tritannus where Daphne is located. Ultimately, Bloom decides to restore Lake Roccaluce but not before stating to Tritannus that their fight is far from over.
- Go Back to the Source: The Source of Sirenix is in Lake Roccaluce, which is where the Winx first began the Sirenix Quest.
- Power Dyes Your Hair: For some reason, the Winx's hair changes color in Sirenix, but only when they are underwater.
- Wham Episode: The Winx finish the Sirenix Quest, entering the Infinite Ocean and becoming Sirenix fairies.
- Where It All Began: To find the source of Sirenix and officially complete the Sirenix Quest, the Winx have to go to the place where their journey began, which turns out to be Lake Roccaluce.
