Alien Nation (1989)

A flying saucer crashed in the Mojave Desert and its inhabitants turned out to be alien slaves, bred to be super intelligent and strong, and controllable by their Overseers. These Tenctonese, or "Newcomers", have been assimilated (sort of) into the population of Los Angeles. One of them, George Francisco, is a police detective with a human partner, Matthew Sikes. George and Matt fight crime together, while learning to respect the other's culture, and question his own. They also fight prejudice, as personified by the Purists, and fear, in the form of the unseen Overseers, who seek to regain control over their slaves.