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.
Woo-jin, a furniture designer who wakes up in a different body every day, falls for Yi-soo, a woman he meets through his work.
Stuntman Cha Dal-geon gets involved in a tragic airplane crash and ends up discovering a national corruption scandal in the process. Go Hae-ri, the oldest daughter of a deceased marine, decides to work for the National Intelligence Service as a secret ops agent in order to support her mom and younger siblings, although all she wanted to do is to become a civil servant.
At Incheon International Airport, brilliant but distant engineer Lee Soo-yeon and clumsy, idealistic rookie Han Yeo-reum cross paths as they navigate tough challenges, personal secrets, and unexpected connections in their new jobs.
