Der Mann im Fenster (2017)

After the separation from his girlfriend, the unsuccessful writer Paul moved into his new apartment. Lonely and lethargic, he tries to divert himself by writing, when one evening he makes a strange observation in a window of the opposite apartment. Despite initial distrust, he does not pay much attention to the voyeur. When he finds a blank Polaroid in his mailbox and gets unanswered calls shortly afterwards, the unpleasant feeling in Paul grows that something may not be right.