When I first came across The Expanse novels by James S.A. Corey, I was under the impression that the science fiction genre was, generally, more fiction than science. And this still holds true for a lot of sci-fi, but there are some works, like The Expanse, that make an effort to stay true to the rules that govern the universe we know. The Expanse takes place in a reality where there are nations on Mars and ring gate that takes you to other galaxies, but it seems believable, and it all seems relatable.

When The Expanse was picked up by Amazon Video, the third season had just come to a close on SyFy. The fourth season adapts the fourth book, Cibola Burn. The crew of the Rocinante are hired by the U.N. to mediate a land dispute between Belter refugees and the Royal Charter Energy company, which is tasked with the exploration of a new planet they have named New Terra. Of course, chaos ensues, in the forms of shootouts, natural disasters, the laws of physics changing unexpectedly, and apocalyptic level disasters. It’s just another chapter in this galaxy-spanning story, one that goes on for five more books, with possibly more to come.

With so much source material to work from, it’s crucial that the producers and showrunners pick the right plotlines to adapt for television. Mostly, they make choices that retain the heart of the story, although there are differences. For season 4, it was decided to keep the character of Marco Inaros — an infamous Belter rebel — at arm’s length, a distant and mysterious threat with a dangerous ambition. He also has a presence via Filip Inaros, his son with Naomi Nagata, one of the main characters aboard the Rocinante. Marco is the driving force behind a plotline that sets up the main conflict for the fifth season of the show. Marco is the main antagonist of the fifth book as well, so that tracks.

In the books, readers come to have a deep understanding of Marco Inaros as a character, seen as he is through the eyes of his son Filip and later Naomi. His plight against the Inner Planets is seen as righteous, though his methods merciless. When his grand intentions are revealed, the reader is left with a sense of betrayal and loss, as if a family member was suddenly revealed to be a murderer. This all happens in the fifth Expanse book, Nemesis Games. We learn of Naomi’s past with Marco, and how they became so different even though they grew up in similar circumstances. The Expanse is telling us that even though people are products of their environment, it’s ultimately their choices that define them.

Unfortunately, this is not the Marco Inaros we get to know in season 4 of The Expanse. The few sequences where he appears are generally quick, and only serve to move the story along to a conflict involving one of the main characters, primarily Ashford and Drummer. When on screen, Marco is a disheveled mess, with a crazed look in his eyes. There isn’t a hint of the cunning and calculating man from the novels. We see a glimpse of his manipulation skills in one scene where he’s being interrogated by officers of the O.P.A. (Outer Planets Alliance). His pleas for his life reach Drummer, a notoriously stubborn leader, and Marco is spared. It’s only in the very last scene of the season that we see the true danger Marco represents. He outsmarts Ashford, killing him and putting his grand plan into motion in the same move. As viewers, it seems like we’ll have to wait until next season to see dynamism of Marco Inaros.

Amazon Video has been producing some of the best original shows of any streaming service lately, (see The Marvelous Mrs. Masiel or Fleabag for confirmation). And although it didn’t begin on Amazon, The Expanse is no different. No longer penned in by time limits or content restrictions, in season 4, the writers were able to give the characters the depth they have in the novels. From Amos and Crisjen’s very colorful language to the frank depictions of violent conflict, the fewer rules the show has to follow, the better the show gets. Right out of the gate, Amazon has done this space epic justice.

There are a lot of genre shows competing for attention right now. In that crowded field, season 4 of The Expanse stood out, and managed to be the best season of the show thus far. It provided the characters with challenges and conflicts that forced personal growth while staying true to the core of who these people are. That’s compelling whether a show is set in outer space, a futuristic Earth in political turmoil, or an alien planet. This is science fiction that is grounded by human problems and relatable characters that make the impossible seem real.

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