Journalist Thomas Geffert from Düren is found dead, and the police suspect suicide. However, Rudolf-Günther Böhnke, a retired head of the Aachen homicide division, is not so sure. What had the deceased, who was investigating a series of mysterious deaths in the German-Belgian-Dutch border region, discovered? Before Böhnke knows it, he is caught in a whirlwind of unresolved murders, apparent accidents, and staged suicides. His investigations take him all the way to Fuerteventura, where he must make the hardest decision of his life.