One of the teachers, Palladium, takes the fairies to Black Mud Swamp to test their ability to communicate with nature, navigating the swamp without magic.
At Cloud Tower, Knut tells the Trix that the specialists are giving their troll to the authorities, and the interrogation sorcerers could find out about the Trix's plan. The Trix plan to free and eliminate the troll.
As Brandon, Sky, Riven, and Timmy are transporting the troll in their ship, the Trix cause them to crash in Black Mud Swamp. As Musa falls for Riven, the specialists see that the troll has escapes. Riven is quite rude to the fairies before they leave. The fairies realize that someone (the Trix) has broken the troll out, and follow his footprints, using the voice of nature when the footprints disappear due to a spell the Trix cast.
The specialists are attacked by vines, which try to eat them. The plants only eat loudmouths, and attack Stella when she deliberately provokes them. Flora gets them to release her, then the specialists when they find them. They decide to work together to find the troll. Riven is reluctant, even when Tecna and Bloom help Brandon and Timmy save him when he falls into a whirlpool.
They find the troll attacking Amaryl and two other girls. The specialists try to recapture the troll but he runs off. Amaryl and the other two girls call the specialists losers and leave. Sky and Riven argue until Timmy breaks it up, and Tecna falls in love with Timmy.
The Trix use a perfume to draw the troll to them. The duck continues to annoy them, and Icy freezes him before the troll arrives. The Trix imprison the troll in the dark dimension, limbo, and return to Cloud Tower.
Only Bloom and Flora seem able to hear the voice of nature. They find the spot where the troll disappeared, and when they detect dark energy, they deduce what happened, and that the Trix are behind it. Although the five are the last to return, their other successes give them the highest score in the class, which annoys Amaryl.
The five decide to come up with a name for their team. At Bloom's suggestion, they agree on the name "Winx Club."
- The troll from the first episode is imprisoned in limbo. (In the RAI version the Trix destroyed him)
- Bloom, Stella, Flora, Musa, and Tecna are now the Winx Club