After ex-Stasi spy Anne Marie Fuchs ( Lina Wendel ) and import and export dealer Youssef El Kili ( Karim Cherif ) successfully solved their first common case with unorthodox methods, Youssef sees himself as an aspiring Sherlock Holmes. Without Anne's knowledge, he had business cards for the young detective agency „ Fuchs & El Kili " printed and distributed them diligently to his customers. Not without success, because in fact he pulls a potential client ashore – very much to the astonishment of the completely unsuspecting Anne, who considers the investigator startup to be a snap idea and initially refuses to support him.
However, it does not take long for Youssef to be in trouble, because on his arrival he finds his client, Astrid Altmann ( Doris Plenert ), dead in her house, what Commissioner Eisner ( Robert Dölle ) calls for and almost results in his arrest. No question, Anne has to help him out of the clamp, because alone Youssef will neither solve the case nor be able to pull his head out of the loop. In addition, working with Youssef is a welcome change from the dark thoughts about her espionage past and the loss of her child for Anne. The dead woman was an active opponent of the lignite opencast mine, which soon became her Heimatstadt Ekenbach is said to fall victim to.
The daughter of the murder victim, Katja Mehring ( Tanja Schleiff ), works for Westdeutsche Kohl AG, which operates the opencast mine and the associated relocation of Ekenbach. Mayor Röpers ( Dirk Borchardt ), the boss of Astrid Altmann, is also shaken. Who would be interested in Astrid Mehring's death and, above all, why did she want to hire a private investigator? To find out, the daughter of the dead Anne and Youssef is now asked to get to the bottom of the matter. When Katja Mehring, the operator of the local gravel pit, is killed shortly afterwards, the situation worsens.
Using highly creative, albeit largely illegal methods, the „ vixen " and Youssef find out, that Carsten Mehring ( Isaak Dentler ) bought land in Ekenbach on a large scale on behalf of a Luxembourg real estate company. But why should someone invest money in a place that will soon be razed? In the course of their investigation, in which Youssef is caught by Anne's approach time and time again, the two are caught in the crosshairs of a number of powerful gentlemen, who want to get the „ sniffer " off their neck – a life-threatening situation for Anne and Youssef.