Susan Duncan is a prominent scientist involved in Neolution’s clandestine cloning projects. She and her late husband, Ethan Duncan, are considered the parent figures of the clones, having discovered the science that made cloning possible. They originally planned to raise Sarah Manning, but their surrogate ran away and hid what turned out to be identical twins. They later came to raise one of the other clones, Rachel Duncan. Foremost a curious scientist, Susan struggled to intimately connect with her daughter. Lacking a mother’s innate compassion, Susan chose the experiment over Rachel and abandoned her to be raised by the DYAD Institute. Reuniting with her daughter after almost 20 years, Susan hopes to make amends.