The time and place
All over space, in space stations and on various planets. I'm not sure about the time.
The suspension of disbelief
Not-Very-Near Human alien races exist and populate the universe. A group called the Controllers has the power to indoctrinate people's brains, except for a race/group called the Shielders. Shielders are persecuted and live in off-grid planets and colonies, hiding from Controller influence.