The first three seasons of The Expanse are the best science fiction television ever made. That’s not hyperbole and it doesn’t require qualification. By the standards that matter — world building, political complexity, character depth, physical realism, sustained narrative tension — nothing else in the genre comes close.
Then Amazon bought it, and the same show with largely the same cast and creative team produced one of the most disappointing fourth seasons in recent memory.
I haven’t seen seasons five and six. This review covers what I’ve seen. The first three seasons earn the 9.5. Season four earns a 4 by itself and only that high because the craft underneath the bad decisions is still visible. This is a review of both: what greatness looks like when it’s working, and what happens to a great show when it stops understanding what made it great.
Physics as Character
Most science fiction treats physics as an obstacle to ignore. Ships bank in turns. Explosions make sound. Gravity is constant and convenient. The Expanse treats physics as the foundation everything else is built on, and that decision changes everything downstream.
In The Expanse, acceleration is the defining variable of interplanetary society. Ships have to burn to move and burn to stop. Communication between planets has a time delay that makes real-time coordination impossible. Living in low gravity for generations produces bodies that can’t survive Earth’s pull. The Belt’s resource extraction economy exists because of the energy cost of lifting mass out of a gravity well. None of this is explained at you. It’s built into how every character moves, speaks, thinks, and makes decisions.
The result is a world that feels extrapolated rather than invented. The political tensions between Earth, Mars, and the Belt don’t come from the writers needing conflict. They come from physics and economics operating over generations. Earth has gravity and resources but is politically sclerotic. Mars has discipline and ambition but is three generations from a habitable surface. The Belt has nothing except the labor that everyone else depends on and the accumulated resentment of people treated as expendable. You don’t need a villain to generate that conflict. You need realistic constraints operating over time.
The best world building doesn’t invent problems for characters to solve. It extrapolates conditions that generate problems automatically.
Pick one or two physical or economic constraints and follow them to their logical conclusions before you write a single scene. The Expanse asked: what happens to human society if space travel requires massive energy expenditure and takes months? Every political, cultural, and personal conflict in the first three seasons follows from that question. The constraint does the work. Your job is to extrapolate honestly, not to invent drama on top of a world that doesn’t support it. If your world building requires you to ignore your own rules to make the plot work, the rules aren’t built right yet.
Political Drama That Feels Real
The political architecture of The Expanse is the show’s second great achievement. The tension between Earth, Mars, and the Belt isn’t a backdrop for the story. It is the story. The Rocinante crew’s personal struggles are interesting precisely because they’re playing out against a solar system on the edge of war, and the war is interesting precisely because every faction’s position is comprehensible.
Chrisjen Avasarala is the best political character in recent science fiction television. She is calculating, ruthless, profane, and entirely committed to a version of the greater good that requires her to do things she finds personally repugnant. She’s not a villain. She’s a person doing a hard job in a system that punishes idealism and rewards cynicism, and she’s made her peace with that without losing sight of why it matters. Her scenes work because the show trusts that complexity without explaining it. You understand her position by watching her maneuver, not by listening to her explain herself.
The Belt factions are equally well-handled. The Belter independence movement is not coded as heroic or villainous. It is coded as a natural consequence of exploitation, which is more unsettling than either framing. The OPA operates with a logic that is internally consistent and externally disturbing. When Belter characters make decisions that horrify Earth characters, the horror is never cheap. You understand exactly why they got there.
Every faction in your story should have a position that is comprehensible from inside their own logic. Not sympathetic, not correct — comprehensible. The moment your antagonists start making decisions that only make sense because the plot needs an obstacle, the political drama dies. Build each faction’s position from their material conditions: what do they have, what do they need, what do they fear losing, what grievance has accumulated over how long. Let the conflict emerge from those conditions. The audience will believe in stakes they can trace back to cause.
Characters Who Earn Their Weight
The Rocinante crew is the emotional center of the show, and they work because each one carries a specific weight the narrative requires. Holden is the moral compass who keeps getting it wrong in ways that cost people their lives. His idealism isn’t presented as a virtue. It’s presented as a flaw that produces genuine consequences, which makes his eventual commitment to harder choices feel earned rather than convenient.
Naomi’s backstory unfolds slowly and deliberately, and when the full picture assembles it recontextualizes everything that came before. That kind of longitudinal character work is hard to do in television because it requires the writers to know where they’re going long before the audience does. The Expanse knew. The payoff is real.
Amos is the most interesting character in the show and the most carefully written. He is operating with a moral framework that he assembled himself from scratch after a childhood that gave him nothing to work with, and the seams show. He is not a sociopath. He is something more specific and more interesting: a man who has constructed ethics deliberately rather than absorbing them, which means his ethics have gaps where the absorbed version wouldn’t. The show reveals this through behavior, not exposition. You work out what’s happening inside him by watching what he does in situations that other characters handle on instinct.
Amos Burton is what happens when a writer understands the mechanism of a psychology rather than just the label. The behavior is specific because the interior is specific. One follows from the other.
The Expanse crew works because each character has a specific relationship to morality, not a general personality type. Holden believes in principles over consequences. Naomi believes in loyalty over principle. Amos has no inherited moral framework and operates on a case-by-case construction. Bobbie believes in duty until duty fails. Those positions generate specific conflicts when they interact. Map your ensemble’s moral architectures before you write their dialogue. The arguments they have will write themselves.
Subtext That Does the Work
The Expanse never stops to explain what it’s about. The class dynamics between Earth, Mars, and the Belt are not discussed in speeches. They’re embedded in how characters speak, what they eat, how their bodies move, what they assume about each other, and what they consider an insult. The Belter creole language is built from the linguistic debris of communities thrown together under pressure, which is exactly how real contact languages develop. The water rationing behaviors, the low-gravity workout regimens, the different relationship to vacuum and radiation: all of it is shown through texture, not told through exposition.
This is the craft achievement that most separates The Expanse from comparable shows. The societal critique is real and pointed — resource extraction, labor exploitation, the casual cruelty of comfortable people toward desperate ones — but it arrives through accumulation rather than declaration. By the time the audience understands what the show is saying about class and power, they’ve reached that understanding through their own observation. They weren’t told. They noticed.
That distinction matters enormously. Audiences resist being told what to think. They embrace conclusions they feel they’ve reached themselves. The Expanse engineers that process systematically across three seasons.
Subtext is not the absence of theme. It’s the displacement of theme from dialogue into behavior, environment, and consequence. Take your theme and ask: if no character ever stated this directly, how would the world itself demonstrate it? What details, what habits, what asymmetries in how different characters are treated would make the theme visible to an attentive reader without anyone naming it? Build those details into every scene. The theme should be something the reader discovers, not something you deliver.
What Amazon Did to It
Season four is a 4 out of 10. From the same show. That gap requires explanation because it’s instructive.
When Amazon acquired The Expanse after Syfy cancelled it, they moved the story to Ilus, a newly discovered planet outside the solar system. The Rocinante crew spends the season on one world, dealing with a land dispute between UN colonists and Belter squatters. The interplanetary political tension that generated the first three seasons’ stakes is reduced to subplot. The sense of scale — solar system-wide, civilizational, irreversible — shrinks to a land management problem on a frontier planet.
The physical constraints that made everything feel real were still nominally present. The craft was still visible in the writing and the performances. But the story had been confined in a way that stripped away the structural elements that made it work. The Rocinante crew thrived in the context of solar system-wide crisis because their personal scale contrasted productively with the political scale. Put them on one planet dealing with one conflict and the productive tension between those scales disappears.
Amazon spent money to save the show and then made decisions that undermined the specific things worth saving. That’s a particular kind of failure. Not incompetence. Not indifference. A genuine misreading of what made the show great, followed by confident execution of the wrong priorities.
Know which structural elements are load-bearing in your story before you change anything. The Expanse’s greatness depended on scale: the contrast between personal stakes and civilizational ones, between individual moral choices and solar-system-wide consequences. Remove the scale and you remove the engine. Before you cut, compress, or redirect any major story element, ask what else depends on it. The thing you’re changing may be holding up more than you can see.
The Collaboration Behind It
The Expanse is based on novels written under the pen name James S. A. Corey — a collaboration between Daniel Abraham and Ty Franck. Abraham brought literary craft and experience with complex multi-threaded narratives. Franck brought world-building instinct and the large-scale political sensibility that makes the series feel like a living system rather than a constructed one.
The collaboration works because the seams don’t show. You cannot read the novels and identify who wrote which section. The voice is unified, which is the hardest thing to achieve in collaborative fiction and the most important. Two writers producing alternating chapters is not collaboration. Two writers producing a single voice is something rarer and more valuable.
The television adaptation maintained that unified vision through the first three seasons. When the show moved to Amazon and the original creative circumstances shifted, the unity fractured. The decline in seasons four onward is partly a story about what happens when the conditions that produced a creative vision change and the vision doesn’t adapt correctly.
If you’re collaborating, the goal is not to divide the work — it’s to build a shared voice. That requires more conversation before writing than most collaborators expect: not just plot and character, but sentence rhythm, what the narrator notices, what humor sounds like, how much interiority is too much. The Abraham/Franck model works because they apparently solved the voice problem completely. You should be able to hand a page to a reader who knows your collaboration and have them unable to identify which partner wrote it. If they can tell, the voice isn’t unified yet.
The Verdict
Seasons one through three of The Expanse are as good as science fiction television gets. The world building is rigorous, the politics are credible, the characters carry genuine weight, and the subtext does serious work without ever stopping the story to announce itself. It is the standard against which other ambitious science fiction should be measured.
Season four demonstrates how quickly and completely a great show can lose what made it great. Not through incompetence but through a fundamental misreading of its own structural requirements. The talent was still there. The conditions that allowed the talent to produce its best work were not.
Watch the first three seasons. They are required viewing for anyone who writes in the genre or studies long-form narrative construction. Watch season four if you want a case study in how structural decisions undermine execution. I haven’t seen five and six. Based on what I’ve read, they partially recover but never return to the heights of the first three seasons. The shortened final season apparently couldn’t land the story in six episodes when it needed ten.
The first three seasons stand on their own. They always will.
For a deeper look at the writing craft behind The Expanse and what makes its storytelling approach a model for ambitious science fiction, see the full analysis at The Writing King.
FAQ
Which seasons of The Expanse are worth watching?
Seasons one through three without reservation. They are the best science fiction television ever produced. Season four is a significant drop and earns a 4 — watchable if you’re committed to the story, but not representative of what the show is capable of. I haven’t seen seasons five and six.
Is the science actually accurate?
More accurate than anything else in the genre. The show commits to realistic physics: no sound in space, ships that have to accelerate and decelerate, communication delays between planets, bodies physically changed by generations in low gravity. It doesn’t use scientific realism as decoration. The realism is the foundation the political and personal drama is built on. Remove it and the whole structure changes.
Why did Season 4 fail so badly?
Structural confinement. Moving the story to a single planet removed the solar-system-scale tension that generated the first three seasons’ stakes. The Rocinante crew’s power comes from operating against a backdrop of civilizational conflict. Put them on one world dealing with a land dispute and the productive contrast between personal and political scale disappears. The craft was still there. The structural conditions that allowed it to work were not.
What makes The Expanse different from other sci-fi shows?
It extrapolates rather than invents. The political conflicts, the cultural differences, the economic tensions all follow logically from physical and economic constraints operating over generations. Nothing happens because the plot needs it. Everything happens because the world is built in a way that generates those pressures automatically. That’s a much harder thing to do than it sounds, and almost no other show in the genre manages it.
What can writers learn from The Expanse?
Six things: build worlds from constraints, not drama. Give every faction a comprehensible position. Map your ensemble’s moral architectures before you write their arguments. Displace theme into behavior and environment rather than dialogue. Know which structural elements are load-bearing before you change anything. And in collaboration, the goal is a unified voice, not divided labor.