I am writing to you from the belly of the beast

In 2022, Minos Efstathiadis receives permission to enter the maximum security prison of Straubing in Germany to meet a prisoner sentenced to life imprisonment.
The interview ends, but during it, a different and unknown case begins to be revealed.
How can the disappearance of a girl in 1981 in the Bavarian forest of Lake Ammer be connected to the murder of a woman in her luxury penthouse in the center of Munich in 2006? The convict is transformed into a narrator and the writer into an investigator. Or perhaps into a real witness?

Frederik Talas stood behind an old, half-rusty gate, which had no guard, and watched me. Objectively, old photos on the Internet could not help in identifying him. The man who shook my hand bore little resemblance to that young man from the past.
"I was expecting you earlier," he told me.
"It was a difficult morning. Everything went wrong."
"That's how it usually goes. Come with me."
Excerpt from the book