Yoon Sung Soo, who knows about the X, wakes up. Sung Soo offers Nabi Team to bring his son if they want to know about what he knows. To earn the evidence, the Nabi Team members go around everywhere to find Sung Soo's son. Meanwhile, Moon Gi feels suspicious about Si Joon and Tae Joon's relationship. Moon Gi orders Mr. Choi to find out about Si Joon.

Si Joon knows the story that Jae Hyun had only told Dong Soo. Dong Soo thinks Si Joon has killed Jae Hyun. Dong Soo asks Young Shim to keep it secret from Si Hyun. They start to look into Si Joon's background. Dong Soo and Young Shim find out Tae Joon and Si Joon's relationship had started from the fire incident at Seosu Building. Nabi Team finds Do Jin's hiding place and sees Mr. Choi locked up inside.

Tae Wook tells Si Hyun that Si Joon had killed Jae Hyun. Although Si Hyun can't believe Tae Wook's words, she decides to take Tae Wook to the Joongki Police Station. Tae Joon goes to the police station to take away Tae Wook. However, he gets stopped by Dong Soo and at last Tae Joon decides to take out his gun. Si Hyun begins her sketch and draws a shocking picture of Si Joon.