The German crime series "Der Kommissar und..." focuses on the mentally very unstable investigator Martin Brühl (Roeland Wiesnekker), who investigates kidnapping cases together with his girlfriend. The LKA psychologist Susanne Koch (Meike Droste) knows how ailing Brühl is and that he has been dependent on psychotropic drugs for some time. This also means that he is sometimes very agitated during his investigations and his work could suffer as a result.