This is so fantastic. When I went out drinking with the writer Clemens Meyer he said the director Andreas Dresen was making a film version of his debut novel Als wir träumten. And he said he hoped he could get a cameo role. This February article in the Märkische Allgemeine gives us a little teaser, and it has an entry on imdb and is in post-production but I can't find a release date.
What you can look at, though, on that Fischer Verlag website 114, is a picture of Clemens in costume as a police officer. With a tiny interview about how he wanted to be a detective on the murder squad when he was a kid, but that became (ahem) impossible. I'm so impressed. It's even better than the larger-than-life painting of him that surprised me in the Leipzig art museum. He's living the dream, that boy is, living the dream.