Half a century has passed since humanity colonized Mars and built an advanced, AI-driven society there. At the center of this new civilization lies Alba City, a place where everyone strives for greatness. Among those aiming for such ambitious heights is 17-year-old Tuesday—a gentle, aspiring musician who has run away from home, carrying only her precious Gibson guitar. As she wanders through the capital's bustle, a captivating song leads Tuesday to Carole, a tenacious girl playing her keyboard on the streets. Although the girls could not appear more different at first glance, their genuine love for music unites them in their endeavor to conquer the arduous path to success in Mars' challenging music industry.