|For the version from Eva's world, see Martha Nielsen|
As a teenager, Martha is a sensitive girl who has a passion for acting and seemingly political activism as well. She once goes on a hunger strike to protest child hunger in Africa. Also within the realm of politics, she seems to be somewhat conspiratorial, as well as antiestablishment, or at least anti-nuclear energy. She believes a nuclear-power mafia keeps things hidden from the public to protect the image of the nuclear power plant, for which she is ridiculed by her brother. To her credit, it eventually comes to light that the power plant has been hiding damaging information from the public for over thirty years.
Martha goes to the lake with her friends Jonas Kahnwald, Franziska Doppler, and Bartosz Tiedemann, along with her brother Magnus. At the lake, Martha and Jonas are sitting together when he finds a pendant with an engraving of St. Christopher imprinted on it. A short while later, he suddenly remembers that he promised to teach his grandmother Ines how to use her new tablet and hurriedly leaves.
Shortly after, Jonas who has traveled from 1921 sits next to Martha. She is surprised he has returned so soon and says he seems different. Jonas tells her they are perfect for each other, and they kiss. Later, at her parents' anniversary party, Martha brings Jonas upstairs and gives him back the St. Christopher's medal from the lake, which she has put on a string. She says, "I thought about what you said at the lake," though he doesn’t know what she means because she is referring to what the time-traveling Jonas said to her after he left. She tells him, "I think you're right," before kissing him. The two have sex.
Martha develops a romantic relationship with Jonas, but during Jonas's extended absence from school following his father's suicide, begins dating his friend Bartosz.
After Jonas's return to school, Martha joins Bartosz, Jonas, and her brothers Magnus and Mikkel in a late night escape to find the missing boy Erik Obendorf's hidden drug cache outside the Winden Caves. Following her brother's disappearance at the cave mouth, and her being torn between Jonas and Bartosz, she becomes increasingly sorrowful in the following days.
After ignoring multiple calls from Bartosz, Martha texts Jonas on the morning of November 7th, wanting to talk with him. After a dress rehearsal of her play, Jonas visits Martha in the dressing room. Jonas confides in her that he was in psychiatric treatment rather than an exchange program in France as Bartosz had been telling their classmates. Jonas then asks why she contacted him rather than Bartosz that morning, and she embraces him in a kiss.
Unaware that Jonas has traveled back in time to 1986, Martha unsuccessfully tries to contact Jonas multiple times during the next two days. Martha confronts Jonas in the pouring rain as he is leaving home. Jonas abruptly tries to leave, but she demands to know why Jonas kissed her only to ignore her afterwards. Now aware that Mikkel is his father, making Martha his biological aunt, Jonas rejects her tersely, unable to explain the impossibility of their relationship. Saddened and angered by Jonas's seemingly cold response, she reconciles with Bartosz after telling him about her meeting with Jonas.
Martha breaks up a fight between Bartosz and Jonas outside their school— the last time she will see him before he disappears.
Martha rides her bike to the bridge where Bartosz is waiting. He tells her he has tried calling her. She tells him there's a lot going on, she has wanted to talk for a while. Bartosz realizes they are done. He tells her it is because of Jonas. She says that has nothing to do with it, he has really changed, she has no idea what is going on with him. He tells her his mother is dying and there are things he can't tell her. She responds that she has to deal with her missing brother and father, and a mother who barely acknowledges her. She tells him it's better this way and leaves.
Martha dreams of her sex with Jonas, who tells her that they are perfect for each other, and not to ever believe anything else. She awakens distressed and bursts into tears.
When Franziska and Magnus decide they want to go to the caves, Martha tells them she sometimes dreams of Jonas and feels he is still alive. They walk into the caves and the ground begins to shake. They hear footsteps. It is Bartosz, carrying a suitcase. They demand to know what he is doing there. Magnus punches him. They open his suitcase and ask him what it is. He tells them it doesn't concern them. Magnus tells Bartosz that if he has anything to do with the disappearance of his brother and father, he will kill him. Martha tells Bartosz they will leave him there overnight, and take the suitcase.
Katharina is looking at the school photo with Mikkel in it. Martha and Magnus come downstairs. Katharina tells them that there is something they need to see but they say they have to go. Martha lashes out at her, demanding to know why all of a sudden she wants to speak to them when she has ignored them for months. Katharina attempts to stroke Martha but she rebuffs her and says they no longer need to talk. They both leave.
The teenagers return to the Winden Caves and are observed by Noah. Bartosz is still tied up there. They ask him what is going on. He says he cannot tell them and even if he did, they wouldn't believe him. Franziska tells him that the human body can survive three days without nourishment, and they all prepare to leave. Finally, he tells them it is a time machine. Magnus does not believe it, but Martha tells Bartosz to show them how it works. Bartosz says he needs a phone. Martha hands him hers. This activates the device.
The teenagers emerge from the cave and realize the landscape is different, the chair is missing. Bartosz says he didn't believe it at first either, but Noah predicted what would happen before it happened: Martha would kiss Jonas, his mother would get cancer, Jonas would disappear only to return later. Franziska says Elisabeth knows Noah. Magnus scoffs and leaves, the others following. Bartosz asks Martha if she trusts him. She does not answer and goes to join the others.
They emerge from the forest and come to the bus stop. Posters advertise a 1987 concert. Police cars drive past, with the elderly Ulrich on board, who recognizes his children and tells the police to stop but they drive on. Bartosz asks them if they believe him now. Martha looks at him and walks off with the others.
Martha returns home and finds the St. Christopher medal on her bed, which the older Jonas sat there.
Martha, having found the St. Christopher medal (left by the adult Jonas) thinks Jonas has returned, as Bartosz predicted. She mentions this to her friends and she and Bartosz argue. She makes it clear their relationship is over.
She heads off on her own to Hannah’s house. While Hannah isn’t there, the adult Jonas (the Stranger) lets her in. Martha asks who he is. She looks at him strangely and he asks if she is scared of him. She says she is experiencing deja-vu. As he did previously, he responds "a glitch in the matrix." He asks whether she found the St. Christopher medal he left for her. She then realizes that he is Jonas.
Sitting at the kitchen table he starts to explain his absence. Martha then says it all makes sense now. She takes his hand in hers and touches his forearm and face. They are interrupted by Katharina who breaks into the house, searching for Hannah. On seeing Martha and Jonas together she pulls them apart and asks Martha whether she knows who this man is: the son of her brother, her nephew. She tells Jonas to keep his dirty hands off her and takes Martha away.
After her death, her corpse comes to participate in several overlapping realities that send Jonas in one direction or another. In one, Jonas abandons her dead body and hides in the basement as the apocalypse engulfs Winden. In another, Jonas is saved just in time by an alternate Martha (who in the other reality does not save Jonas because she is stopped by Bartosz Tiedemann of her world); Jonas takes one last look at Martha's body before traveling to the other world. Finally, Adam returns after having spoken with Claudia Tiedemann in the future and saves Jonas from the apocalypse in order for him to destroy the knot once and for all, again leaving Martha's body behind.
- Episode 1: "Secrets" (2019)
- Episode 2: "Lies" (2019)
- Episode 5: "Truths" (2019)
- Episode 6: "Sic Mundus Creatus Est" (2019)
- Episode 9: "Everything Is Now" (2019)
- Episode 10: "Alpha and Omega" (2019)
- Episode 1: "Beginnings and Endings" (2020)
- Episode 4: "The Travelers" (2020)
- Episode 5: "Lost and Found" (2020; 1987, time travel)
- Episode 6: "An Endless Cycle" (2019, slightly younger)
- Episode 7: "The White Devil" (2020)
- Episode 8: "Endings and Beginnings" (2020)
- Dark Season 2 Episode 8: "Endings and Beginnings"
- Dark Season 3 Episode 8: "The Paradise"
- Dark Season 1 Episode 1: "Secrets"
- Dark Season 2 Episode 6: "An Endless Cycle"
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- Dark Season 1 Episode 9: "Everything Is Now"
- Dark Season 1 Episode 10: "Alpha and Omega"
- Dark Season 2 Episode 1: "Beginnings and Endings"
- Dark Season 2 Episode 4: "The Travelers"
- Dark Season 2 Episode 5: "Lost and Found"
- Dark Season 2 Episode 7: "The White Devil"
- Dark Season 3 Episode 6: "Light and Shadow"
- Dark Season 3 Episode 7: "Between the Time"