Hibiki and Kanade decide to enter a music contest together. On the day of the contest, they realise they don't have a piano to perform on, but their friend Waon Nishijima helps them out. However, it is soon revealed that the contest is a trap laid out by Bassdrum who spreads the Melody of Sorrow and creates some Cymbal Negatones. As Hibiki and Kanade struggle to fight against it, a mysterious masked Cure known as Cure Muse appears and ensnares the Negatones, allowing Kanade to purify them.