While desperately searching for his missing daughter, Hae-kwan comes across an AI satellite robot that remembers sounds from all over the world. Rejuvenated by the robot's abilities, Hae-kwan begins to track down his daughter's voice. As they continue their journey, they form an unforgettable bond.
이성민
as Hae-Gwan
심은경
as Sori (voice)
이하늬
as Ji-yeon
채수빈
as Yoo-joo
이희준
as Jin-ho
김원해
as Goo-cheol
류준열
as Underground Singer
전국환
as President Go
곽시양
as Hyeon-soo
전혜진
as Hyun-sook
이영진
as Yoo Sung-jin
강진아
as Jang Geun-yeong
