The themes of the movie Bladerunner.
Search for Identity
The main character of the movie, Rick Deckard, eventually comes across a woman that he proves to be a replicant. A sub-plot is then formed about her trying to find meaning in her life. Later in the movie Deckard is revealed to be a replicant and it is implied that he flees the city with the replicant Rachael.
Bladerunner takes place in a bleak future where urban sprawl has covered the planet and the weather mostly consists of rain due to the large coverage of clouds created by gas pumped into the atmosphere. People that haven't left for off-world colonies deal with a crime-filled, murky, and smog-y existence.