Iginio Straffi initially outlined the show’s plot to last three seasons. He chose to continue the story for a fourth season in 2009. Around this time, Winx Club’s popularity attracted the attention of the American media company Viacom, owner of Nickelodeon. Viacom purchased 30% of the show’s animation studio, Rainbow SpA, and Nickelodeon became a co-producer of the series. Production on the fifth, sixth, and seventh seasons was divided between Rainbow and Nickelodeon Animation Studio. To attract an American audience, Viacom assembled a voice cast of Nickelodeon actors (including Elizabeth Gillies and Ariana Grande), invested US$100 million in advertising for the series, and inducted Winx Club into Nickelodeon’s franchise of Nicktoons.