You (Jung Haneul) are an undercover cop trying to bust an underground smuggling ring called EXO.

Your cover is a bartender working at a run-down pub where some of the EXO members secretly gather to drink. Your mission is to gain membership to EXO, but so far, all of the undercover agents have been exposed and killed. Not only that, many people want to join EXO who are on the rise as the most profitable gang in Seoul.

But you're determined to get into EXO to bring them down. This job cost you the love of your life, Oh Sehun, a police officer who broke up with you after you went to jail as a cover to meet the owner of this pub.

Sacrificing Sehun was the hardest thing you had to do in your years as an undercover cop, where you have to keep your job a secret and only one person knows of your true identity: your handler, Kim Joonmyun.

Luckily, you meet into a man named Kai who is a small fry in the gang. He makes a living off collecting debts and delivering rice. Despite his status, Kai is determined to climb to the very top and he turns into your opening to join EXO. Right now, your biggest priority is to become Kai's underling and you're throwing your all out --- including using flirty tactics to seduce the ambitious yet strangely down-to-earth Kai. But will things get complicated when you get closer to Kai and find out he's not all he makes himself out to be? If you begin falling for him, it won't be just your life on the line when your cover is blown, but your heart as well...