: The unit's top lieutenant who disguises himself as Bang Dong-gu , the village idiot. He perfectly executes his "fool" persona by falling down stairs daily and acting mentally challenged, all while secretly being a lethal combatant.

The story follows three highly trained agents from the North's elite "5446 Corps" who are sent to the South to await reunification orders while posing as ordinary residents.

: An agent posing as a rock star trainee, despite having no actual musical talent.

: A young agent who infiltrates a local high school . He looks up to Ryu-hwan as his hero and mentor.