|“||My name is Rachel Duncan, and we are going to come to terms.||„|
|~ Rachel Duncan|
Rachel Duncan is one of many clones in Orphan Black. However, unlike the other clones in the series, Rachel was raised self-aware by the Dyad Institute - her creators. Dubbed a "proclone" by Felix, the adopted brother brother of series protagonist and clone Sarah Manning, Rachel is still working with her creators within the Dyad and is trying to bring the other clones under their wing.
Little is known of Rachel's childhood. However, in a videotape that Sarah found in Rachel's apartment, it is revealed that she was raised in Cambridge, England by Professors Ethan and Susan Duncan, her adoptive parents. It also appears that Rachel had a very happy childhood and was loved by her parents, as she is seen playing with them.
Rachel first appears in "Unconcious Selection", the ninth episode of Season One. However, her face, and therefore the fact that she is a clone, is not revealed until the next episode, the finale of the first season, whereupon Sarah is taken out of police custody and brought to Rachel at the Dyad Institute. Rachel tries to get Sarah to sign a contract with the promise of answers and protection for Sarah and Kira, Sarah's biological daughter. When Sarah refuses, Rachel asks her to take 24 hours to reconsider.
Later, Sarah calls Rachel and tells her that she doesn't want Kira to live the way she has, to which Rachel agrees and Sarah agrees to come in. However, Cosima Niehaus, another clone, tells Sarah that Rachel's offer of freedom is a lie and that all the clones have a patent written into their biological code. Sarah sends Rachel a text message saying "Up yours, Proclone" and runs to get to Kira. Upon seeing this message, Rachel makes a phone call to an undisclosed person and says simply, "You know what to do." When Sarah returns to her adoptive mother's house, she finds it ransacked while Kira and Mrs. S, her adoptive mother, are nowhere to be found. It is implied that Rachel's phone call was the order to kidnap Kira and Mrs. S.
While Sarah is on the run from Dyad, Rachel calls Sarah using Paul's phone and tells her that Sarah can see Kira and Mrs. S again if she surrenders herself. Aldous Leekie, a scientist at Dyad involved in the handling of the clones asks Rachel, if she actually kidnapped Kira and Mrs. S. She tells him the less he knows, the better. He asks if they even need Sarah and she tells him that they do. During a party at the Dyad, Sarah, disguised as Cosima, goes down to Rachel's office.
Without turning to see who's entered her office, Rachel knows it is Sarah. When Sarah demands to see her daughter, holding a gun, Rachel tells her that when her people arrived at Mrs. S's house, they were already gone. Rachel tells her calmly, "You're not going to shoot me, Sarah." Sarah then shoots a glass plant holder very close to Rachel's head, making a scared Rachel back away from her. Rachel tells Sarah that there are others after the clones and that together they can find Kira. Sarah strikes Rachel across the face and knocks Rachel to the ground. Sarah kneels down and holds the gun to Rachel's face. Rachel tells her that nobody lays hands on her, then Sarah tells her that Rachel doesn't own Sarah and the other clones.
Later, Cosima has started working on the Dyad's clone project in order to find a cure for the genetic illness suffered by her and Katja Obinger, yet another clone. Rachel shows Cosima the results of her latest medical exam from University of Minnesota. It shows a high lymphocyte count, much like Katja. When Cosima asks to examine the original genome, Rachel tells her that is impossible and that Cosima's health problems stem from the cloning procedure. She then gives her data on Sarah's upbringing and her sequenced genome. Rachel wants to find why Sarah can procreate naturally while the others cannot.
She later goes to her room where it is being cleaned after the murder of one of her monitor, the person assigned to each clone to watch over them and send reports back to Dyad. Rachel looks disturbed when she notices the videotape of her childhood in the VCR. Leekie tells her that all this is a result of her heavy-handedness. She tells him that she's only begun. She tells Paul, the ex-monitor of both Sarah and another clone - Beth, that she needs a new monitor now that Daniel is dead. She tells him that even though she has been self-aware since childhood, she is not exempt from the program. After Leekie tells her that he's had some success in creating a cure for Cosima's illness, she tells him to halt the test; "until Sarah gives herself up, Cosima will suffer". While watching the videotape of her childhood again, Rachel tells Paul that Sarah's trying to learn everything about her, like Rachel is trying to learn everything about Sarah. She also tells Paul that even though he reports her data to Leekie, he works for her. She tells him that when her adoptive parents died, Leekie became like a guardian to her. She then gives Paul a gun. It is assumed that she then has him frame Felix for the murder of Daniel. Later that night, Rachel has Paul in her apartment and manipulates him into sex.
Later on, Rachel comes to Mrs. S's house with Paul to meet with Ethan Duncan, her adoptive father, who she assumed had died in a fire many years earlier. Mrs. S tells Rachel that she has 15 minutes to talk with him and that if anyone makes a move on her house, she will kill Ethan. Rachel sits at the kitchen table with Ethan and he explains to her what really happened to her adoptive mother, Susan Duncan. It is revealed that Leekie was responsible for the fire that killed her. Ethan asks Rachel to forgive him and she starts crying. Later, at the Dyad Institute, Rachel is standing in her office when Leekie enters. Rachel tells him that her father sends his regards. Realizing that Rachel knows the truth about her parents, Leekie tells her that he had no choice because the Duncans were going to run away with Rachel and because they set the science of cloning back decades. While Leekie is standing next to her, Rachel calls Marian Bowles, her boss, on speakerphone where they talk about how it has been arranged for Leekie to be killed. After hanging up, Rachel tells a scared Leekie to leave and that if he doesn't get in his car or go home, he might survive. She tells him that it's foolish to help him but she does it because Leekie raised her.
- Rachel is multi-lingual. She is seen speaking German, and it is implied that she knows Mandarin Chinese