In Our Prime

In Our Prime is a 2022 South Korean drama film directed by Park Dong-hoon. The film stars Choi Min-sik, Kim Dong-hwi, Park Byung-eun, Park Hae-joon and Jo Yun-seo and revolves around two people: a genius mathematician with a hidden past and a student who is failing math. It was released theatrically on March 9, 2022.

Premise
Lee Hak-seong (Choi Min-sik), a genius mathematician who defected from North Korea in search of academic freedom, hid his identity and story. He lives as a security guard at a private high school where the top 1% of gifted children gather. One day, Lee Hak-seong, who is the number one target to be avoided by students due to his cold and blunt expression, meets Han Ji-woo (Kim Dong-hwi), a high school student who gave up mathematics begging him to teach him mathematics after learning his identity. While teaching Han Ji-woo — who was wandering in a world looking only for the correct answer — how to find the correct solution process, Lee Hak-seong also encounters an unexpected turning point in his life.

Cast

 * Choi Min-sik as Lee Hak-sung, a school security guard and defector from North Korea who is said to have proven the Riemann hypothesis.
 * Kim Dong-hwi as Han Ji-woo, a student who asks Lee Hak-sung to teach him math.
 * Park Byung-eun as Kim Geun-ho, math teacher.
 * Park Hae-joon as An Gi-cheol, agent of the National Intelligence Service who monitors Lee Hak-sung and the owner of a junk shop that is a front office.
 * Jo Yun-seo as Park Bo-ram, Ji-woo's classmate.
 * Tang Jun-sang as Lee Tae-yeon, Lee Hak-sung's son.
 * Kang Mal-geum as Han Ji-woo's mother
 * Kim Hee-jung as Park Bo-ram's mother

Special appearance

 * Joo Jin-mo as Oh Jeong-nam, a mathematician who participated in an international math competition with Lee Hak-sung when they were young.
 * Kim Won-hae as Park Pil-ju, a North Korean defector and Economics professor.

Box office
, the film has a gross of US$4,081,864, and 534,287 admissions.