In one sense, the science fiction elements are pretty limited. There weren't spaceships, faster than light travel, teleporters, ray guns or sharks with frikkin' laser beams. There were some genetically modified creatures, a Star Trek style food replicator and that's about it.
But it was set in a post apocalyptic US where the political situation is radically different. There's a Capital that is very much in charge and there are twelve Districts that are geographically and politically isolated.
And part of the way the Capitol shows its power is by having a Shirley Jackson style lottery where two "winners" from each of the twelve districts are dropped into an arena where they fight to the death. Why? Because that's the way the bastards in the Capitol want it.
Come to think of it, it's a pretty absurd premise, really, but it never feels absurd because the characterization and the storytelling are absolutely first rate.
Read it. You won't be sorry.