Sarah (Tatiana Maslany), a wandering orphan, witnessed a woman committing suicide. Because she looked very similar to the deceased, she decided to pretend to be the deceased to receive a considerable amount of savings. However, Sarah never expected that she would break into a dangerous mystery. While "playing" the dead, Sarah discovered an astonishing fact: she and the woman who committed suicide were actually clones, and there were more than two of them. In order to achieve their ulterior motives, the illegal organization created a batch of cloned embryos and implanted them into ordinary couples who were unaware of it, allowing them to be born and grow in different environments. No one knows who created these clones, and no one knows their ultimate purpose. These clones must find out the truth as soon as possible, otherwise it will be too late, because an assassin is assassinating them one by one.