Commissioner Krüger is feverishly looking for three film students in the Hochwald. They wanted to make a film based on a Sorbian legend and the unexplained disappearance of two women. The students are initially swallowed up by the ground. What remains is your laptop, on which your filmed film scenes are stored. With these clips, Commissioner Krüger tries to clarify these two, widely divergent missing cases. Mirko, Laura and Dennis, the three film students, want to make a semi-documentary, semi-fictional film. To do this, they use the folk tale of Nix, a Aquarius who lives in the waters of the Spreewald with his wife, daughters and sons. Legends report that when the mermaid is hurt, he draws his victims to his wet realm. They never reappear.
Mirko found an old case, to which the film should build. Fifteen years ago, two young women disappeared inexplicably in the Spreewald. The students go on a search, interview locals and the then responsible commissioner, summon the legend and poke around in the old case, encounter interest, skepticism and open rejection. When Laura and Dennis find that their fellow student Mirko is the son of one of the two missing women, they themselves are in danger. But getting out of the Nix project is out of the question. His initially reluctant assistant Fichte and a Polish cleaning lady help Krüger to gradually see through the student's production and to recognize the connection. Krüger attaches himself to the trail of a suspect.
But then comes a fateful storm night.