In a hospital in Hamburg, an unidentified woman is disconnected from the life-support system. While the investigators search for the mysterious perpetrator, two more men are murdered.

For Neele and her life partner Steff, the dream of having one's own child finally seems to come true: Steff is pregnant. However, there was a confusion in the artificial insemination - instead of their carefully selected sperm donor, they caught a sperm donation from a gay couple: Kalle and Jens also want a baby and consider the confusion as a kind of coincidence. While the two men look forward to their time as active fathers, Neele and Steff see their harmonious trinity at risk.