Unexpected. 

They're a group of 7 of the best spies from Seoul's biggest underground secret society, MYSTERY. It consists of Han So Eul, Lee Cheon Eun, Park Hye Su, Lee Han Ri, Hwang Ji Hae, Song Iseul, and Kwon Elise.

Give them any target, and it's extinct in moments. Nothing is impossible for them. Or so they think.

Now, their next target is INFINITE, one of South Korea's rising boy bands. Their company, Woollim Entertainment, is run by a CEO who apparently murdered MYSTERY's chief in command.

Enraged, the girls are ordered to wipe them off the face of the Earth completely as a way for MYSTERY to avenge their rivals. To do so, they must do the unexpected: form an idol girl group called Mystique, befriend the 7 heartthrobbers, and destroy them.

Wait, did you say GIRL GROUP?!?! Yup. And one that gushes a cute, aegyo-filled concept that will capture the hearts of fanboys all over Korea. Too bad no one else knows who they really are.

Sounds easy enough for the people who have spent their life slaughtering criminals and protecting the city of Seoul. But what if obstacles cross their way? Obstacles like jealousy, bitterness, scandals, friendship, and maybe, just maybe, even love?

Life isn't always what it seems, now, is it? 

;)