What if your friend was murdered and the police wouldn't investigate?

Israel, 1950 - When private detective Adam Lapid runs into Yosef Kaplon on a crowded Tel Aviv street, he can hardly believe his eyes.

The last time they met was in Auschwitz. They were prisoners together in the same barracks. Then one day, Kaplon was gone. Adam was sure he was dead.

Soon after Kaplon tells Adam his remarkable story of survival, he's found dead in his apartment. The police say it was suicide, but Adam isn't so sure. He decides to investigate the matter himself.

Did Kaplon really take his own life? Or has Adam stumbled on the trail of a serial killer who is hunting a unique sort of victim?