The Heart and The Sword is the ninth episode from season 3.
After the events on Eraklyon, the Winx girls return to Alfea, with Bloom upset of what occurred. Compounding their situation soon afterwards are a group of parents who demand that Bloom be expelled from school citing the claims of Diaspro and the attention from Valtor. While Ms. Faragonda is completely against such communication, Bloom concedes and returns to Gardenia, upset from the events on Eraklyon. However, her voluntary expulsion is short-lived. Stella shortly arrives with news that Prince Sky has announced plans to quickly marry Diaspro. Bloom returns to the realm of Magix and quickly devises a plan, with the help of the specialists, to approach Sky and determine that something is wrong with him.
After some diversionary tactics, the Winx Club (minus Tecna and Layla, who stay behind at Alfea) encounter Prince Sky, who launches himself into a fight with the Winx girls. The fighting continues until the Winx girls manage to subdue Sky, and notice Valtor's mark on his shoulder. Stella uses her Enchantix powers and fairy dust to try and break the spell. However, additional guards, led by Diaspro, arrive to defend Sky. This forces the Winx girls to retreat to Alfea before they can ensure that Stella's fairy dust was effective.
At Alfea, they are once again catched by Assistant Principal Ms. Griselda for their unauthorized excursion. Returning to their rooms, they encounter Layla, who is upset with the news that her parents have decided to enforce an arranged marriage for her, with a boy named Nabu that she has never met.