Yong hears a stranger's voice from the future, connecting them to each other and sharing their love stories.

Ditto

A story about three friends who just turned twenty; an age where you can do whatever you want, love whoever you want with opportunities abroad.

Twenty

Cha Ra-Ri (Kim So-Hye) hears that her boyfriend Im Gun-Hyeong died and she is devastated by that news. She decides to kill herself, but first she wants to complete a bucket list that she wrote with her boyfriend. Around this time, she happens to meet Kang