Overview

After his mother's death, 16-year-old Hyung-ju suspects that his father is not his biological father. A secret paternity test reveals that he is not. Confused, he uses his math skills to figure out his biological father and embarks on a journey with his best friend, Ji-su, to find him.

Top Cast

J

Jeong Da-min

Hyung-ju

Kwak Min-kyu

Min-hyu

Kim Se-won

Ji-su

Seo Suk-kyu

Woo Yeon-seo

Min-joo

Kim Jae-u