In the Shadow of Memory (1999)

Emir is sleeping at his girlfriend Seren's house. Seren wakes Emir up and tells him that she is going to the hairdresser. Emir does not want to be alone because he was kidnapped in the past. He tries to convince Seren to stay with him, but he fails. Shortly after Seren leaves the house, Seren's neighbor Eren appears at the door. Emir remembers the voice of Eren. Eren is the person who kidnapped Emir in the past. Emir waits for Seren in fear. Seren comes back after a while. But Eren never acts suspicious. Seren tells Emir that he was not kidnapped, that they were all in his head, that he had suspected others before, and that they could no longer see them. The reason they couldn't see them is that Emir himself kidnaps the people he thinks kidnapped him. And his last victim is his neighbor Eren.