The twins Cyrus and Adeline look like two drops of water only on the outside. Their characters are as different as the colors of yin and yang. After the tragic death of their parents, the twins are found in an orphanage. Fifteen-year-old sisters are going to be adopted. But the director of the orphanage, who did not like the bully Adeline, insists that Kira will be better in a new family without her troubled sister. After listening to this conversation, Adeline decides that if she is lucky enough to have only one, she will be this sister. Adeline is intoxicated by Kira with pills and leaves the orphanage instead.
Fourteen years later, fate brings the girls together again, but the new acquaintance lasts a few days - Kira is killed right in front of her sister. Adeline decides to do anything to find the killer, but for this she needs to become Kira again.