A man either committed suicide or he was murdered. An autistic girl is the only witness.

HONG Gildong is an infallible private detective with an exceptional memory and quirky personality. While chasing the only target he failed to find, he gets entangled in a much bigger conspiracy than he bargained for.

A love story about the 70-year-old romance novice Sungchil, the flower seller who moves his heart Geum-nim, and the people who cheer them on.