Now in its fourth season — with a fifth incoming — “The Expanse” is the greatest science-fiction series that you’re not watching.

The series originally aired for three seasons on Syfy starting in 2015, before being resurrected by Amazon Prime after its cancellation following season three. As with many great shows, ratings dictate a quicker demise than creativity — and there was still much more story to be told. Thankfully, Amazon stepped in and rescued the show, bringing all three Syfy-produced seasons to its Prime streaming service, along with a new fourth season that released in December.

“The Expanse” is based off a series of novels written by James S. A. Corey — a joint pen name of authors Daniel Abraham and Ty Franck, who are longtime collaborators and editors for “A Song of Ice and Fire” author George R.R. Martin. The series is set in the future, when humanity has colonized Mars, the asteroid belt and some outer planets of the solar system. Interstellar travel is still out of reach, but the expanded reach of humanity has opened new avenues for resources and opportunities. That expansion has also created splinter factions within humanity. The United Nations of Earth; the Mars colony; and the “Belt,” a collection of loosely-aligned factions of humans living and working in the asteroid belt, are constantly on the verge of war with each other. It’s against that ever-changing backdrop that the events of the first three seasons of “The Expanse” play out.

“The Expanse” is to science-fiction as “Game of Thrones” is to high fantasy. The show grounds its fantastic premise in as much real-world science as possible and uses it to tell an interwoven story of politics, betrayal and discovery. Don’t go into this show expecting the optimistic futuristic vision of “Star Trek,” or the borderline science-fantasy elements of planetary exploration and meeting new alien species on an episodic basis. Humans are still confined to the solar system and are constantly on the edge of total annihilation as they fight with each other as much as the elements of the deep vacuum of space.

The first season can be tough to penetrate and enjoy on a first watch. The show throws so many characters at the viewer with little initial background or exploration. The viewer is dumped right into the middle of this sprawling universe and is expected to pick up the breadcrumbs of world building and character development as you go. Part of that is due to the show trying to combine too many elements of the first two books and cramming them together in 13 episodes.

There are three interconnected storylines: Miller, a belter cop looking into the disappearance of a rich businessman’s daughter; Holden and his crew, a group of survivors from a destroyed ice hauler at the center of the conspiracy; and Avasarala, a major politician in the UN who navigates tensions between Earth and Mars. Each storyline takes a little time to get moving, but they all begin to connect, and later expand, as they circle a massive conspiracy that involves the possibility of alien life. Though, don’t expect humans with minor facial prosthetics to stand in as aliens.

Each season builds upon the last, cranking up the action and the stakes. More characters are introduced in later seasons, but the show does a much better job of easing them into the storyline to make it easier to follow. If you can last through the first season, which really starts to get good during the second half, then you’ll be hooked for the remainder of the show’s run up to this point. Those first six to seven episodes just require a lot of patience as the show does a lot of heavy world building during its introduction.

Similar to “Game of Thrones, “The Expanse” uses its setting as a backdrop for many modern political and cultural parallels. Much of the early seasons are dedicated to the conflict between the working class and the elite. At times, it delves into politics in warfare and offers commentary on the brutalities of war. It even touches on human exploitation and racism. Even several hundred years in the future, humanity still faces these basic issues. Politics are at the center of the story, and the thrills of space combat and ware are matched equally by the commentary on the human condition and the political machinations of many characters.

“The Expanse” does admittedly run into some pacing issues, especially toward the end of season three and into season four. After tackling the main story arc of the first two books, the series plows through elements of the third book rather quickly. That’s because this book is the weakest in the franchise and is merely setup for what’s to come. It creates a hiccup in the pacing, but will bear fruit as the show continues.

“The Expanse” takes a little while to get moving, but it’s still the best science-fiction show currently available. Even if you’re not a genre fan, there’s enough here to entice many to at least take a look. Like “Game of Thrones,” “The Expanse” transcends traditional genre entertainment to be something better. At 49 episodes — all available on Amazon Prime — it’s a good time sink for anyone looking for a new show to pass the time during quarantine.

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