When Yoon Bomi loses everything that she loves, she abandons her job as a royal family agent in order to pursue one goal: kill the man who took everything from her. But when the princess recruits Bomi for a special team to take down the Shadow Clan, the clan whose purpose is to kill the princess and take the throne, Bomi finds herself torn between the shadows of her past and the light of her future.

Apink has always relied on their beloved leader, Park Chorong, but when she is involved in a terrible accident, the members must learn how to cope and heal without their leader's help. Friendships are tested, secrets are revealed, and bonds are broken.