Back in 1998, Joon Hee's bubbly personality shines through Min Joo. Those around her begin to notice — including a mysterious figure who watches from afar.

Si Hun finds himself attracted to the new Min Joo. The love triangle grows when he decides to come clean to Jung In gyu.

Joon Hee tries to warn the boys of the approaching danger. Meanwhile, a horrifying event takes place at school during the night.