The dark part of the past does not fade away as long as one does nothing actively against it. Kenan Ender, a Turkish professor living in Istanbul, is on the verge of completing his most important project: the creation of the perfect food, flawless and complete in its composition of high-quality nutrients. After a long time, he returns to Vienna to attend a congress; he also comes to finally put the past behind him. During his stay, a murder occurs. The suspicion falls on him. Harry Deckardt from the Vienna Criminal Police takes on the case and travels to Turkey with his extremely health-conscious partner Manfred Knödig to interrogate the professor. There, they are supported by Chief Inspector Hülya Baylan and her colleague, who are also in the process of solving a case.