Polt muss weinen (2001)

Real estate speculator Albert Hahn is found dead in his cellar. He died of fermentation gas poisoning. The doctor in charge assumes it was an accident. But Polt knows that the dead man was hated in the community. He suspects that the murderer wanted to make the death look like an accident. Many of the winegrowers had a motive. After a long investigation in the wine cellars, he discovers that all the cellars are connected by holes. Polt doesn't want to leave the feeling that it was a murder. As he drinks some wine with his friends, they all confess to the crime. They had all poisoned Albert Hahn with the fermentation gas together, but only one of them wants to take all the blame, as the rest have children and wives. He commits suicide and leaves a confession behind.