Love Revolution (2020)

S1E17 Kyung-woo Is Missing

Kyung-woo vanishes for two days following a run-in with some old friends from middle school. When he finally shows up at school, he seems cold and unfriendly towards Joo-young. Determined to uncover the mystery behind his sudden change in behavior, Joo-young and their other friends delve into memories from their middle school days to piece together what might have affected Kyung-woo during his absence.