The Element of Crime (1984) on Netflix

A European police detective living in Cairo undergoes hypnosis therapy to deal with headaches caused by his last case. He recounts spending two months in a dystopian Europe investigating the serial killings of young girls who sell lottery tickets. While the current police force there employ clumsy methods, he continues to use the controversial theoretical methods of his now disgraced former mentor. He becomes obsessed with a suspect from previous similar killings, and using an old surveillance report retraces the steps of that suspect. As the journey progresses, the differences between the cop and the serial killer become blurred.