This story contains spoilers for season 1 of The Expanse.

There are two kinds of realism in science fiction: scientific accuracy (which is always debatable when it comes to space travel), and social insight. If you’re lucky, you’ll get one. And if you’re watching The Expanse, returning for its second season tonight on Syfy, you’ll get whopping doses of both. Plus you’re in for one helluva ride.

Based on the bestselling novels by James S.A. Corey, pen name for the crack writing team of Ty Frank and Daniel Abraham, the series follows the adventures of an interplanetary ice hauler crew 150 years in our future. On a hum-drum run between the asteroid mines of the Belt and water-hungry colonies of the inner system, they find themselves drawn into a conspiracy that could spark a war between Earth and Mars. But from the earliest moments in its first season, it was obvious that this show wasn’t going to be your typical space adventure. Sure there are explosions, zero-gravity antics, glowing blob zombies, and swashbuckling heroes, but there is also a rich, rewarding social world to explore.

The future of power

Maybe the best way to put it is that this is a show for political junkies who want to escape from real-world politics. There are several new powers at play in this future world, and they make today’s troubles with nationalism look like a distant dream. Despite environmental catastrophes, Earth is a superpower, and it's home to the system government at the UN. Mars is a hyper-technological society devoted entirely to the rigors of terraforming in the hope that one day their citizens will breathe freely on the planet’s surface. Their military tech is unparalleled. Meanwhile, the asteroid belt, known simply as the Belt, is basically a Deadwood-style frontier. It’s full of poverty, corruption, and exploited miners riddled with all the diseases that come from living in low gravity with cheap climate controls.

As Earth and Mars jockey for power, and the Belt chafes under their yoke, the whole system is basically a tinderbox waiting to explode. That’s where protagonist Jim Holden (Steven Strait) comes in. He sets off the first flare with—what else?—a viral video full of unintentionally fake news.

Holden, the executive officer on the ice hauler Canterbury, decides to answer a distress call. While Holden and a small shuttle team investigate, the Canterbury is mysteriously vaporized by a stealth ship of unimaginable capabilities. Believing they’ve been attacked by Martian marines, Holden sends out a video describing what happened. He and the shuttle crew—engineer Naomi Nagata (Dominique Tipper), trigger-happy mechanic Amos Burton (Wes Chatham), and Martian pilot Alex Kamal (Cas Anvar)—figure they’re going to die, too. But instead, they’re rescued by Martian marines, who manage to prove their innocence too late. Holden’s video clip accusing the Martians of blowing up his ship has made it all across the Solar System.

This foments tensions at the UN, where Earth representative Chrisjen Avasarala (Shoreh Aghdashloo) quickly realizes there’s something fishy going on and starts making secret inquiries. More spectacularly, it causes violent protests all across the Belt, especially on planetoid Ceres. Belters have long been the downtrodden working class for the rest of the system, and a radical separatist group called the OPA wants the Belt declared a sovereign power.

Thoughtful world-building

Unlike your typical Star Wars story, where there are Good Guys and Bad Guys, each with their singular purpose, The Expanse is savvy about how messy politics can be. For most of the first season, we were plunged into the strange world of the Belt, whose political factions are at each other’s throats. We see this world of enclosed habitats and space stations, loosely linked by shaky shuttles, through the eyes of tired, corrupt Belter cop Joe Miller. Living on graft and booze, he’s scorned by his colleagues and viewed as an Earth toady by his Belter brethren.

As an example of the thoughtful worldbuilding that goes into this show, we’re treated to small but key details about the Belters’ environment. First, there are a few scenes where people pour liquids that flow into an odd S-shape in the air before splashing down. This is a subtle but awesome reference to the way gravity is generated in the Belt by spinning up asteroids or space stations to create centrifugal force with its gravity-like effects. True, the effect here is exaggerated for storytelling purposes. But at least we’re not dealing with hand-wavey gravitons.

The other terrific detail about Belter life is that citizens of the Belt speak a creole language, invented by linguist Nick Farmer, which reflects the distant origins of these frontier dwellers. It’s a mix of European, Asian, and African languages, plus some sign language, which together give us a pleasing sense of social realism. With just that one touch, The Expanse reminds us that the Belt is a land of poor and sometimes desperate immigrants, just like frontier towns in the Americas once were.

OK, enough about how nuanced and thoughtful this show is. Because there are also the aforementioned glowing blob zombies, which also helpfully cause infected people to barf up crystals, which looks really gross and scary. Remember that distress call that Holden answered, thus setting in motion an interplanetary incident and people’s uprising in the Belt? Well, it was part of a conspiracy between evil UN honchos and even more evil execs at multiplanetary megacorp Mao-Kwikowski Mercantile. They all want to get their hands on a glowing goopy “protomolecule” found in the outer solar system.

Guessing that the protomolecule could change the course of human evolution, Mao-Kwikowski Mercantile starts doing dangerous experiments with it on Belters, taking over a small space station to infect everyone on it and see what happens. Meanwhile, they engineer the Canterbury explosion to distract the people of Earth and Mars. But there’s just one problem. Julie Mao, the daughter of Mao-Kwikowski Mercantile’s CEO Jules-Pierre Mao, has defected from Earth, disowned her family, and joined the OPA resistance on the Belt. When she tips the OPA to her father’s secret project, the OPA sends her out to find out more—and unfortunately, Julie becomes patient zero in the glowing blob zombie protomolecule experiment.

The dark side of posthumanism

Season two begins just as Holden and his crew, now on a stolen (sort of) Martian ship called the Rocinante, discover the experiments and as Chrisjen discovers the political machinations behind it. Miller has met up with the crew of the Rocinante because his last job as a cop—before being booted off the force—was to find Julie Mao. So now the gang is all together, an asteroid called Eros is full of twitching, glowing zombies, and Earth and Mars are on the brink of war.

I’ve had a chance to watch the season premiere that airs tonight, and it promises to be just as intense as last season. We’re focusing in on Mars this time and learning a lot more about what motivates its people and political factions. After a narrow escape from Eros, Miller and the crew of the Rocinante have to figure out what to do with their discoveries about the protomolecule. And Chrisjen is going rogue, because she’s realized that her bosses at the UN are plotting something horrific.

There are so many things about this show to recommend it, but this season I’m impressed by the way the writers have brought realism even to the posthuman dream of “rapid evolution” that the protomolecule represents. Normally this kind of theme would be ripped from a Utopian essay about how biotech will help us live forever. I love that The Expanse has taken Silicon Valley-spiced cant about going beyond our bodies and put it in the mouths of executives who order an entire space station’s population to be liquidated in the name of scientific progress.

Most of all, I appreciate that every character is a shade of gray, and every planet or asteroid has a diverse set of factions who are hardly of one mind about what to do next. This is a richly imagined future that doesn’t shy away from showing us the dark side of humanity. Without that necessary darkness, we would never be able to discern the heroism, however compromised, of the Rocinante crew. They have checkered pasts and are sometimes downright destructive, but they want justice for the victims of the powerful. Somehow, their moral ambiguity makes this message about goodness feel more realistic than any political drama today.

The Expanse airs Wednesday nights on Syfy in the US; in the UK, it should be available through Netflix soon.

If the audio above doesn't give it away, Ars Technica's Decrypted podcast will be following along with The Expanse every week! Tune in for commentary from our staff along with special guests including writers and cast from the show, space experts, science fiction writers, and more!

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