Jeong Hae Seong captures everyone's attention with his looks, charm, and smile; Hae Seong is an elite NIS agent on a secret mission to uncover the hidden gold of the Joseon emperor; uncovering the truth behind Byungmun High.

Jeong Hae Seong captures everyone's attention with his looks, charm, and smile; Hae Seong is an elite NIS agent on a secret mission to uncover the hidden gold of the Joseon emperor; uncovering the truth behind Byungmun High.

Hae-seong uncovers a crucial clue hidden within the old building, but Chairwoman Seo quickly learns its potential connection to the elusive gold bars.

Hae-seong attends the anti-bullying committee session with a key witness who clears his name; Dong-min finally finds the courage to stand up for himself.

Hae-seong and the team grow increasingly concerned that Su-a's suspicions could threaten his undercover mission; Hae-seong defies the odds and successfully gains a spot in the student council.

The school's security guard dies, leaving Hye-seong a notebook belonging to his missing father; the revelation is a shock and he storms the NIS for answers.