After years of research, Adolf J. Köppel put together an immutable mosaic of circumstantial evidence that without a doubt convicts the murderer. The non-fiction book "Der Gruber War's" (Gruber did it) leaves no questions unanswered.


Derived from the mosaic of circumstantial evidence, Adolf J. Köppel wrote the crime novel "The Lark's Call", which presents the life and tragic death of the beautiful farmer's daughter Viktoria Gabriel and her family down to the smallest detail. 


The Lark's Call

The gripping crime novel based on the Hinterkaifeck murders

Underneath this crucifix, a peasant family of five and their maid lie in a family grave. All of them had their skulls smashed in. The extremely brutal murderer did not even stop at Josef, who was only two and a half years old. He killed the boy with a single blow through the roof of the pram. The criminal police assumed a sixfold robbery-murder, although all the money was left behind. The neighbours of the murdered family, however, suspected a man from their village of having committed the heinous act. He wanted to marry the beautiful farmer's daughter, but her father did not allow it. Did that man kill the whole family out of revenge, or did someone else have a dirty hand in it? Someone who was so close to the murdered family that no one paid any attention to him...

Der Gruber war's

Non-fiction book on the complete investigation of the Hinterkaifeck murder case

Currently only available in German



This non-fiction book is not based on a six-fold robbery-murder as previously assumed, but on a five-fold murder that took place within the Hinterkaifeck family. It was not an outsider who was responsible for the terrible deed, but the tyrannical and brutal head of the family: Andreas Gruber. It was he who on March 31, 1922, killed his wife, the maid, his daughter and their two children.

But if this man is supposed to have killed the people, how can it be that he was lying with the murdered people on the day they were found?

Did the local guide Lorenz Schlittenbauer have anything to do with the matter?

Did he come across the still living murderer during a patrol, and if so how did the murderer die?

And if Lorenz Schlittenbauer hunted down the alleged murderer, why didn't he call the police and explain everything to them? 


The book contains:

  • New evidence
  • New pictorial material
  • Instructions for converting the mattock into a murder weapon
  • Reenacted injuries
  • Sketched sequence of events
  • Sketched hiding places of the murder tools
  • Sketched sequence of events in the accident
  • Sketched sequence of the cover-up
  • Letter to the Schlittenbauer family
  • Hinterkaifeck today