IOI,at first glance they might look like an average student with a bad attitude.However they are more than that.

Student at day,gangster at night.

Lead by their leader Im Nayoung,who rumour to be the person with no emotion making her the most feared one.

Kim Sejeong,the player.Also the group second best fighter after Nayoung.

Kim Chungha,the dancer.The third best fighter in the group.Expert at using gun.

Jung Chaeyeon,the visual.The group plan maker and doctor.

Zhou Jieqiong,the distraction.Also the group plan maker and weapon specialist.

Kim Sohye and Kang Mina,the mischeive duo.Sohye is a sniper and Mina as the bomb specialist.

Choi Yoojung and Kim Doyeon,the odd couple.Kim Doyeon as the swordsman.

Yoo yeunjung.the group hacker.Also the brain of the group.

Jeon Somi,an all rounder.New addition to the group.