In Our Prime

Ji-woo, an outcast in a prestigious private high school, does not fit in due to his different social background. One day, he meets Hak-sung, the school's security guard who is actually a mathematical genius who defected from North Korea. Ji-woo asks Hak-sung to teach him math and although reluctant at first, Hak-sung eventually agrees. Finding each other in their most difficult times, they open up to one another during their special math lessons.