Soo Min and Eun Ho are having a meeting with Sister Hae Min who claims to know the way to bring back both of their lost memories but with a risk. Eun Ho decides to participate in the ritual desiring to identify the cause of her lost memories and Soo Min also agrees. In the flashback, Soo Min and Eun Ho first make acquaintance and find more about each other through a volunteer project at a remote island.