"Melodies of the Heart" follows the journey of Seungmin from Stray Kids, who is captivated by a fan at their Melbourne concert. Amidst the excitement of the tour, he spots her in the crowd, their eyes meeting for a fleeting moment that leaves a lasting impression on him. Unable to forget her, Seungmin searches for a way to connect but is unsuccessful. When the band's Sydney concert arrives, he hopes to see her again, and to his delight, she's there. What begins as a chance meeting sparks an unexpected bond, leading them to connect through texts and calls in the weeks that follow.