Tom, a greeting-card writer with a deep belief in true love, is blindsided when his girlfriend, Summer, unexpectedly breaks up with him. As he tries to make sense of their 500 days together, Tom embarks on a journey of self-reflection to understand where their relationship went wrong. Through his memories and emotional ups and downs, he revisits the moments that once seemed perfect, but also reveals the deeper truths about his own desires and dreams. Along the way, Tom learns not only about love and loss but also about rediscovering his own passions and what truly matters to him.