In the vibrant realm of Major Land, where music fills the air with magic, Hummy, the feline songstress, readies herself to perform the 'Melody of Happiness' during the grand annual concert. However, the harmony is shattered by Mephisto, ruler of Minor Land, who alters the score into the 'Melody of Sorrow,' a tune of despair. To counter this malevolent melody, Hummy seeks out the Precure, valiant fighters with a deep love for music, to restore joy to the world. Her quest leads her to Kanon Town, the hometown of Hibiki Houjou, a sports-loving musician, and Kanade Minamino, a diligent pastry chef. Despite their past friendship, Hibiki and Kanade have drifted apart, engaging now only in constant quarrels. Their discord is interrupted by Siren, the enchanting songstress from Minor Land, who transforms a crucial musical piece into a monstrous threat. Driven by the shared desire to safeguard their cherished bonds, the girls morph into the Suite Precure! As these legendary defenders, Hibiki and Kanade must set aside their personal differences to preserve the world's happiness.