Martin Gruber seems ready for his "new life". He has made a truce with Anne, left the Gruberhof and has moved into a small apartment. But he is and remains a doctor with body and soul, which is why he devotes all his heart and soul to his little patient Leo Wimmer. The baby, who is only six months old, has high fevers again and again, his parents Jakob and Sabine are very worried. Leo's laboratory values don't look good either. Martin suspects an inherited immune disease, but a genetic examination of the parents does not provide any findings. But one Surprising realization: Jakob is not Leo's biological father. Kathi Wimmer, Leo's adult sister, is visiting Ellmau to introduce her parents to her new boyfriend Tobias Ritter. When Sabine and Tobias see each other, they are both visibly shocked. They already have each other met once – nine months before Leo was born Sabine wants to remain silent, but Martin is sure: Only the biological father ka nn still save the baby. And Sabine has to tell the truth about that. Because Kathi and her father Jakob still have no idea about Sabine's secret. Martin's daughter Lilli is still not sure whether working on the farm or in the practice is right for her and therefore decides to divide her time up in the future. Business at the Gruberhof is finally starting up again, not least thanks to Anne's zest for action. But Hans and Anne have only been business partners for 24 hours before they are at odds again. And of all things, Martin, who was called to help by mother Lisbeth, is now supposed to mediate between the two stubborn heads. He's not only completely tied up in professional matters, but also in matters of love. Because Rike absolutely wants to spend more time with him – just like her son Lukas. At a meal together, the situation with the teenager escalates. Although Lukas later apologizes to Martin at his mother's urging, his joy is limited when Rike suggests spending a few days together as a couple. Martin's friend Kahnweiler, on the other hand, would be happy if his Vera would finally get in touch again. She's been hiding with a friend for a week because she wants to clear up a few things. Does that mean the end for the two?

Luck in disguise for Martin Gruber. Because although Lukas left him alone and badly injured after his fall on the mountain, thanks to Anne's efforts, Martin is found. But while he is still in the hospital, he closes in on his family and rejects Lisbeth's offer to come back to the farm to recover. The situation with Anne is still easy to deal with. Although he is still visibly shaken, Martin throws himself into his work as passionately as ever. One case particularly affects the Bergdoktor. Since the death of her mother, 16-year-old Alina has been living with her father Daniel Förster, his wife Petra and their son Finn. When the depressed girl wants to end her life with pills, the consequences could hardly be worse. Because her little half-brother Finn accidentally poisoned himself with the substances when he drank from Alina's glass. Both children then collapse with severe organ damage. The only chance of salvation is a liver transplant, and as soon as possible, because Alina and Finn's condition is deteriorating rapidly. Only father Daniel comes into question as a donor, but the bad news from Martin and Kahnweiler hits him like a punch: he can only donate part of his liver to one of his children, so he has to decide whether he wants to save the life of Alina or Finn. His wife Petra asks him to decide for her son. But he doesn't want to let Alina die either, especially now that they are about to finally build a father-daughter relationship. When Daniel is about to do something stupid, Martin has an idea. Is there hope for both children after all?