The first three episodes of The Expanse’s fifth season will hit Amazon on December 16, so you still have plenty of time to return to the frontiers of space and revisit season four (or more if need be). But in case you’d rather read a quick refresher instead, we’ve got you covered.
Most of The Expanse season four—the series’ first on its new home on Amazon after being brought back from cancellation over at Syfy—took place on Ilus, a frontier planet accessed using the Ring Gate, an interstellar passageway that leads to dozens of new solar systems.
Tasked by Earth’s glamorous UN Secretary-General Avasarala (Shohreh Aghdashloo) to keep the peace between Belter settlers and the security forces of an Earth mining corporation, both of whom are intent on claiming Ilus’ valuable lithium deposits, the Rocinante crew—Captain James Holden (Steven Strait), mechanic Amos (Wes Chatham), engineer Naomi (Dominique Tipper), and pilot Alex (Cas Anvar) encounter trouble almost immediately. Both sides are heavily armed and very reluctant to compromise. Even worse, Ilus itself is riddled with structures left behind by the ancient beings who built the Ring Gate using protomolecule-based technology—the protomolecule being the dangerously unpredictable alien substance that’s propelled much of The Expanse’s action so far. Humans can’t control it, much less fully understand it, though that doesn’t stop them from trying.
As the artifacts begin to “wake up,” everyone’s soon embroiled in the cataclysmic chaos that follows. All the while, Holden is in psychic communication with Miller (Thomas Jane), who technically died in season two but then transformed into a protomolecule-powered avatar with two masters; he’s occasionally helpful (when he’s “Miller”) but usually just frustrating (when he’s “The Investigator”). By the end of season four, we still don’t know much about the protomolecule builders—and we know absolutely jack shit about the malevolent entities that wiped out the builders’ civilization millions of years ago, other than the fact that there’s no guarantee they won’t suddenly appear and do it again.
Beyond Ilus, there were several smaller (but no less important) side stories in season four. One followed Avasarala’s bid for re-election against the formidable Nancy Gao (Lily Gao). We also followed disgraced military hero Bobbie Draper (Frankie Adams) as she reluctantly turned to a life of crime back on Mars—only to stumble across a conspiracy involving corrupt Martian military members in cahoots with bad-news Belters.
Speaking of Belters, season four also gave us our first quality time with terrorist Marco Inaros (Keon Alexander), who happens to be Naomi’s ex. His extreme tactics are off-putting even to fiery Outer Planets Alliance (OPA) operatives like Ashford (David Strathairn) and Drummer (Cara Gee), who believe the Belt’s tenuous peace with “the inners” (Earth and Mars) is the best way forward for their people. Marco, a charismatic zealot, isn’t willing to give up the fight, which puts the entire system at risk. When Marco is captured, Drummer casts the deciding vote to spare his life—a move she sees as politically necessary, even though she loathes the guy. She soon feels responsible when one of Marco’s chess moves results in the destruction of a Belter ship, and she quits her position as head of Medina Station—the Belter outpost closest to the Ring Gate—in disgust.
Drummer is also one of few characters who knows that years ago, Marco forcefully took custody of the child he had with Naomi: the now-teenaged Filip (Jasai Chase Owens), who is very much his father’s son based on the brief glimpse we get of him in season four.
The season four finale, “Cibola Burn”—named for the fourth book in the James S.A. Corey series of Expanse novels that the show is adapted from—wraps up the crisis on Ilus pretty neatly. With Miller’s help, the protomolecule machines are “switched off” just in time to stop sabotaging the ships in the planet’s orbit, not to mention endangering the lives of everyone on its surface. The Roci and its crew are battered at the end, but they’re all safe, on the mend, and preparing to face whatever’s next. The protomolecule, of course, is still lurking...as is the increasingly urgent question of who or what annihilated the civilization that built the Ring Gate.
On Earth, Avasarala loses the election to Nancy Gao—but since she isn’t ready to walk away from politics yet, she agrees to serve as part of Gao’s transition team. As she’s taking one last look around her old office, she gets an urgent message from Bobbie, letting her know that “there’s something rotten on Mars” involving weapons trafficking between the Martian military and Belters. In space—doing detective work that just so happens to align with the thread Bobbie’s been pulling—Ashford discovers that the Belter buying from Mars is Marco Inaros. Marco has also been gathering a fleet of asteroids, which Ashford deduces are to be used as massively destructive projectiles. But what’s the target?
While Naomi is reaching out to Fred Johnson (Chad Coleman), the powerful OPA leader who runs the Belt’s Tycho Station, for help in tracking down her son, we see Marco and Filip capture Ashford. Before he spaces the aging captain, Marco delivers an enigmatic little sendoff in which he chuckles at Ashford for not catching onto his plan: “You can’t even imagine it. This has always been a problem for our kind. Even our dreams are small.” Except Ashford has caught on to the plan, to late to save himself, but we see him recording Marco’s speech and transmitting it as he takes his last breath.
In season four’s final moments, we get the long-awaited reveal of Marco’s big dream: the asteroids, coated in Martian stealth tech that’ll make them nearly impossible to detect, are heading straight for Earth.
No spoilers here, but given The Expanse’s track record of adapting its source material fairly faithfully, with some necessary streamlining along the way—Ty Franck and Daniel Abraham, who write the novels together as James S.A. Corey, are closely involved with the series—it seems likely that the fifth book, Nemesis Games, will be the main point of inspiration, as well as the novella that digs into Amos’ backstory, The Churn. In a recent interview with Entertainment Weekly, showrunner Naren Shankar offered a tease that’s more thematic than plot-related:
“The theme really is about the sins of the past. To one extent or another, that’s every single storyline, whether it is Naomi personally confronting the fact that she had a son with this very charismatic, and now quite violent, revolutionary-type leader. Whether it’s Amos connecting to his past, or going back to Earth for reasons that we’re not quite sure of. Whether it’s Holden’s past with unleashing the protomolecule. Whether it is the past geopolitical history of the Belt, and its relationship with the inner planets, which we see through Avasarala.”
Here on io9, we shared the first clip from season five, showing Holden going toe-to-toe with Fred Johnson over that little stash of protomolecule Fred’s been holding onto for his own reasons. If we’ve learned anything in four seasons of the show so far, it’s that wherever the protomolecule leads, confusion and tragedy often follow.
There’s also that juicy trailer that was released during New York Comic Con, which gives us a dramatic Marco speech in which he claims responsibility for an “attack” against “our oppressors” (with a shot of Earth in the crosshairs, eep!). There’s also Amos talking to Avasarala about a visit to Earth to handle some “personal business in Baltimore” and a direct reference to The Churn; Drummer finding Ashford’s abandoned ship; Fred Johnson advising Holden he should stop trying to save the world—and also informing Naomi that he’s tracked down Filip; and Avasarala desperately trying to protect Earth even though she’s no longer in charge.
The recent announcement that The Expanse will end after season six is a bummer—and how are they gonna handle cramming books six through nine into one season?—but that’s a bummer for another day. Right now, we have all of season five to look forward to, and it’s almost here! We’ll have more Expanse coverage as we get closer to the December 16 premiere of the first three episodes, and then we’ll have even more Expanse when it shifts to a weekly format starting December 23.
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