Watch on Soap2day. Private investigator Tamer Bakiner dares to try an unusual experiment: he tries to go underground himself. Is this even possible without leaving any traces behind? "On the trail of the truth" - that is the motto of experienced private investigator Tamer Bakiner. During his elaborate undercover missions, he regularly delves into the most diverse milieus, tracks down witnesses and perpetrators - and documents their perfidious methods. His investigative research is often decisive in ensuring that the perpetrators are caught in cooperation with the authorities and the truth comes to light.