“Critical Mass” is the best episode in The Expanse, but not for the expected reasons. It delivers the long-awaited meeting between hard-boiled space detective Josephus Miller’s (Thomas Jane) and reluctant ship captain Jim Holden (Steven Strait,) but it’s the sad and poignant tale of Julie Mao (Florence Faivre) that gives this episode some lasting resonance.
Up until this point, Mao has been persona non grata acting as a plot device to move the show forward. Her story comes to us through Detective Miller and the pieces of information he gleans in investigating her disappearance. The surface details make for a rather flat story of a rich girl rebelling against her father and getting in over her head. Up until this point, it was puzzling that Miller would care so deeply for her. She’s a person that he’s never met before and for all intents and purposes could be dead already so his admiration comes off as odd.
Perhaps it’s a matter of perspective, but seeing the truth of what happens to her puts his motivation into sharper focus. Now there’s some truth to the narrative about Mao. She’s definitely out to oppose her father, but her motivation is not just personal. Mao is genuinely committed to the Outer Planets Alliance and wants to prove her passion for the cause is real. Aboard the Scopuli, she seems to have carved out her place amongst the OPA for they treat her as one of their own despite her upbringing as someone from earth.
It’s her idealism that Miller fell in love with. She exudes a sense of purpose that comes with believing in something which he lost to some extent after seeing the worst of humanity on Ceres station for so long. She pays the price for that idealism as it leads her headlong into the worst kind of trouble. Her reward for meddling in her father’s business is seeing her friends and OPA comrades get beaten or killed by members of her father’s company who we now know are the true enemies trying to ignite a war between earth and Mars.
What bothers Miller about Mao’s story and becomes his motivation to investigate this case is the fact that she was out in space somewhere, out there alone. His anger toward the Outer Planets Alliance and their leader Anderson Dawe stems from his belief that she died for a cause led by self-serving people. What actually happens reveals every bit of that truth. There’s a feeling of dread and isolation when she’s stuck by herself in the hold of a ship full of enemies, desperately trying to contact anybody for help. Then comes one of the most powerful moments of the show, when Mao comes face to face with whatever it was that Holden and the Rocinante crew encountered on the Anubis.
The story becomes sad after she has the sense to hide the Anubis and the thing that’s on board before heading to Eros Station. Mao becomes sick from whatever it was aboard the Anubis but manages to find someplace to hide on the station. She ultimately dies alone, afflicted by whatever consumed the entire crew of the Anubis, wondering why those she trusted never came to help.
Watching that history before Miller and Holden walk into her hotel room on Eros makes that moment when they see her dead such an emotional moment. For all the complex politics and big ideas that The Expanse explores, it’s this moment and Mao’s story gives the show depth.
The rest of this show deals with the aftermath and Miller and Holden put both sides of the story together. They have little time to get to know each other as Eros station is suddenly put on lockdown and all the good guys are left to find a way off the station. The real bad guys finally reveal themselves in this episode and provide a bookend to Mao’s story. A creepy scientist played by Daniel Kash shows up at her body to take samples of whatever it is that killed her then breaks the bad news to her father. She’s stripped of all humanity both literally and figuratively as an alien consumes her and in death, she is simply thought of as a test subject that will further the aims of her father’s company.
While Mao’s story and the aftermath takes up most of this episode, it also pays attention to the side characters and sets up some interesting things for them. Worth noting is Chrisjen Avasarala (Shohreh Aghdashloo) paying respects to her dead friend, the Mars ambassador who committed suicide after her actions got him banned from the planet for life. It turns out he was murdered after discovering some key information about the bad guys. The other revelation comes from Fred Johnson (Chad L. Coleman) who reveals that the ones responsible for attacking the Donnager are from earth.
“Critical Mass” will be remembered because it’s the one that delivers a satisfying payoff to the central plot threads that The Expanse did a masterful job in building. For all the moving parts to the story of Julie Mao, it would have been such a letdown if they failed to resolve the central mystery surrounding her disappearance in a satisfying way. The fact that it does so makes everything else leading up to this so much better.