A bad day gets worse for young detective Murakami when a pickpocket steals his gun on a hot, crowded bus. Desperate to right the wrong, he goes undercover, scavenging Tokyo’s sweltering streets for the stray dog whose desperation has led him to a life of crime. With each step, cop and criminal’s lives become more intertwined and the investigation becomes an examination of Murakami’s own dark side.
near the beginning of the movie, when Murakami (the rookie) is tailing the pickpocket, after the two of them walk down the empty street, there is a scene where the lady is laying her head down on her arms in the foreground. In the background off to the left, there is a window or something with flashing light behind it. It doesn't flash into the room, but it is there.
Possibly? A big theme of the film is post-war disillusionment following World War 2. There's a lot of talk about the war and about how it affected different people or generations differently.
There is a (vague) description of a cat being intentionally stepped on, with the sound of a meowing(hungrily though, not really yowling in pain) cat played over it.