Joon Hee tries to make sense of Min Joo's recollections that get jumbled up with her own. Nam Si Hoon discovers a new side to Min Joo.

As Joon Hee struggles to distinguish reality from her dreams, she receives an old diary that contains a shocking truth.

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.