Hyun Jiwoo, who had to let go of the person she loved during her immature days, is trying to heal her old wounds and start a new love. However, the woman she broke up with in the past, Oh Yeona, suddenly reappears in the worst possible way. The relationship, which becomes increasingly tangled like a thread, is heading towards catastrophe... What will Hyun Jiwoo see after emerging from the long tunnel?