Sara Aoyama, a broke and desperate single mother who wishes to live with her daughter Moe in peace, witnesses the shocking suicide of a woman who looks just like her. When she decides to steal the woman's identity to run away from her problems, she unlocks a world of secrets and a whole heap of trouble. Sara discovers she doesn't just look like this woman, she's genetically identical: a clone - and she's not the only one. As she finds more clones just like her, she comes to see them as a family. Sara must protect them, and herself - because someone is trying to kill them, one by one.
Sara Aoyama (Ji-young Kang), a poor single mother and an orphan one day witnesses Shiina Maoko killing herself by jumping in front of train, that woman happens to be her doppelganger. She takes on her doppelganger's persona but later she find out that there are more doppelgangers of her trying to track her down.