Undercover cop Im Sae-byeok has one job: use his baby-faced charm to infiltrate a university and get close to Ma Leo, the elusive grandson of a notorious gang boss. But on day one, he gets blackout drunk and wakes up next to a mystery man he definitely doesn’t remember. Things only get messier when he discovers he’ll be living under the same roof as both Leo and Leo’s overly clingy best friend, Son Yi-gang. With cockblocks, close calls, and suspiciously attractive housemates at every turn, Sae-byeok’s mission quickly spirals into chaos. Operation Leo might just be his wildest assignment yet.