Season 4: Cibola Burn
"Nothing you do now will stop what's coming."
Despite having the same great characters, the same basic situations, and the same storytelling style, to me Season 4 almost feels like a spin-off series for reasons difficult to articulate succinctly. A fair amount of time is spent on an alien planet, which ought to be exciting, and it is at first. But as the problems besetting Holden and the Belter colonists pile on, the season gradually becomes turgid and bogged down with technobabble. In particular, the concept of "two ProtoMillers" is overly-complicated and tough to swallow.
But my biggest gripe has to do with casting. First, Lily Gao as Nancy Gao has about as much personality as a moist sponge; they really needed to cast someone who could convincingly go toe-to-toe with Shohreh Aghdashloo, which would admittedly have been a tall order. Far worse, however, is what happened to Arjun Avasarala: replacing Brian George with Michael Benyaer proved to be disturbing in multiple ways. For starters, he looks so much like Paulino Nunes, who played Hank Cortez, the priest aboard the Thomas Prince in Season 3, that I spent quite a while thinking it was the same actor, which was a real mind-twister: why would they recycle the priest as Arjun?
So, okay, I understand that Brian George was unavailable when production resumed, which made recasting necessary. But why in the world did the writers also choose to completely change the nature of the character? Previously, Arjun was a gentle, caring soul who provided his wife with an emotional sanctuary from the harsh political world; the "new Arjun" is stoic, insensitive, and driven by a political agenda that often clashes with hers. In short, he went from a loveable gentleman to an insufferable asshole, and it made me wonder what Chrisjen saw in him. I suspect it was done to give Chrisjen a more adversarial partner against which to play, perhaps to make up for a lack of human drama, but sadly it all just came off as unpleasant. Not to mention the fact that, losing a "safe haven" for Avasarala also meant the viewers lost one as well. We need a place to rest just as much as the characters; the episodes otherwise become exhausting. (One wonders, had Brian George been available, if the writers would have made him as annoying as Michael Benyaer...)
That's not to say I disliked the season; there's much to recommend it. Burn Gorman as Adolphus Murtry, for instance, is outstanding, and creates an excellent counterpoint to Holden as well as an alternate-reality mirror of Amos. And despite being the "bad guy," one cannot help but feel a little sorry for him once in a while, which is the mark of great writing and acting. Then we have Keon Alexander as Marco Inaros, whose performance is almost disturbingly good: he demands your attention every time he appears on the screen. As written, he comes off as just a tad over-the-top, but then, as the leader of a revolution, he must be larger-than-life by definition.
One other big plus this time is Clinton Shorter's dark, powerful "New Terra theme" (for lack of something better to call it), which pops up here and there during the season, and also plays under the disc menu.
We do have a regrettable farewell: Sadavir Errinwright won't be around to menace anyone anymore. Which is kind of sad—I'll really miss that "treasonous piece of shit" (Avasarala's word choice).
- "New Terra"
- "Jetsam"
- "Subduction"
- "Retrograde"
- "Oppressor"
- "Displacement"
- "A Shot In The Dark"
- "The One-Eyed Man"
- "Saeculum"
- "Cibola Burn"
SEASON SCORE: 
Trivia: Season 4 episodes have no recaps ("previously on The Expanse"). I thought it was because they were released online instead of broadcast on cable. But, Season 5 episodes have them. A mystery.
Hard Media Extras: Making up for the paltry offerings of Season 3, this batch includes "After Shows," which are roundtable discussions of each episode. Hosted by Steven Straight, they feature producers, writers and cast members—see the individual episode reviews for details. In addition, there are four good docs on the last disc:
- A New World on Mars
- It Reaches Out: ProtoMiller's Point of View
- Script to Screen: The Rocinante Landing
- Art Meets Science at Blue Origin
Original book cover art by Daniel Dociu.