A true Cinderella story on TV if ever there was one, The Expanse went from the limited resources of Syfy for its first three seasons before receiving a massive boost in scale and ambition for its final three. But whether it was negotiating through political deals or engaging in dogfights in space, the series never lost sight of its sociopolitical foundations. Like the best sci-fi, The Expanse uses dense world-building and the idea of unexplained scientific phenomena to examine human nature. And in this case, humanity proves itself quick to draw lines in the sand and adhere to a hierarchy, as if colonization is something that needs to be expanded and reinforced when the universe opens up, rather than abolished. The Expanse is also notable for somehow still looking so good despite mostly being set in cold, metallic interiors and the colder emptiness of space. It's a great example of a show using its visual effects smartly, using spectacle ultimately to clear the way for its characters to take center stage. Some of these characters have rockier arcs than others or are given far less to work with, and the series' treatment of its final antagonist is too simplistic given how thoughtful its politics usually are. But there's more than enough interesting conflict among these characters' social and political differences to make watching them rewarding.

The series' fourth season—its first after moving to Prime Video—stands out as The Expanse's most different batch of episodes. Taking place mostly on a hostile alien world rather than Earth, the Belt, or the confines of a spaceship, the show takes full advantage of this exciting new setting to have characters rely purely on trust (or cunning) to survive. Even here, the series doesn't lose its themes of humanity being reduced into tribes, and of differences in race and class ultimately being created by humans themselves. It's an ambitious move for an established series, but it's one that really gives it new life.