After traveling across the entire planet and finding no one else, Kororu realizes she is truly alone. Overwhelmed by sadness, she discovers a string stretching up into the sky, beyond the reach of her sight. Filled with wonder, she spends the night holding onto the string—only to wake up to a tug from it. When Kororu understands that someone might be trying to communicate with her from among the stars, she becomes determined to climb the string and meet the person at the other end.