Rolf Larsen (40) is a police officer working in the Crime Investigation Department in Copenhagen (CID). He and his wife Maria (34) recently had their first child, Andrea. Just as Maria is returning to her stewardess job after her maternity leave, Rolf is called to work. A baby girl with a heart-shaped birthmark, Minna, has been kidnapped from a nursery in Brøndby, and Rolf is to investigate the case. 
The police immediately suspect the child’s father, a refugee named Zaid, as the mother has won custody of Minna against his wishes. The hunt for the man sets in but for some time all the police can find is the girl’s clothes.  
Suddenly, Zaid shows up at the mother's house, upset and scared. When he realizes that the police is watching the place, he tries to escape, but Rolf manages to grab him and he is brought in for interrogation. Rolf learns that Zaid has a very solid alibi. Meeting the father is a turning point, which convinces him that Zaid is innocent. Rolf feels a strong connection to the case, as it could have been his own daughter disappearing from the nursery.
He now follows alternative traces. Against his boss' command, Rolf takes the story to the press. He feels the police needs all the help it can get from the public to find the child. 
Together with forensic technician Jarl Thybo (50) Rolf starts to collect DNA tests from the area around the nursery. They soon find details that indicate he might be right…