The Expanse Season 4 Finale Just Set Up a Potential Apocalypse

[Warning: The following contains spoilers for The Expanse Season 4. Read at your own risk!]

Well, we finally know what Marco (Keon Alexander) wanted all of that Martian tech for.

When Ashford (David Strathairn) tracks down and is ultimately taken captive by Marco, Naomi's (Dominique Tipper) terrorist ex, in The ExpanseSeason 4 finale, Ashford confronts Marco about his plans for the asteroids he has collected. Ashford believes Marco intends to throw them at Tycho and Ceres Stations as revenge on Fred Johnson (Chad Coleman), Anderson Dawes (Jared Harris), and the mainstream Outer Planets Alliance. However, Marco reveals Ashford has it all wrong: "This has always been a problem for our kind: even our dreams are small."

Marco -- with his and Naomi's teenage son Philip (Jasai Chase-Owens) watching on -- floats Ashford after their cryptic chat. But the former pirate managed to pull off one final act of heroism before he died, sending out a recording of his conversation with Marco.

The Expanse Season 4 Review: Thank God Amazon Saved This Show

With Ashford removed as an obstacle, Marco moves forward with launching the asteroids, which have been painted with the Martian stealth tech that Bobbie (Frankie Adams) and her crew helped smuggle off Mars. And Marco was right -- Ashford wasn't thinking big enough, because he didn't throw the asteroids at any station in the Belt, he threw them right at Earth.

So what does this mean for Earth and everyone who's on it? We know that Avasarala (Shohreh Aghdashloo) is on Luna at the time of the attack (thank GOD!) but her husband, Arjun (Michael Benyaer), insisted on staying behind after the strain her political campaign put on their marriage. The future leader of Earth, Nancy Gao (Lily Gao), also remains on the planet's surface, not to mention the literally billions of people whose lives are now endangered by what are essentially multiple bombs of an unimaginable scale that have been specifically modified to avoid early detection.

So, will Marco's plan work or will Earth's asteroid spotter notice them in time? We'll keep naively hoping for the latter until proven otherwise, because if the asteroids do make it to the surface, the question won't be how many people will die -- it will be whether anyone will be able to survive at all.

The Expanse Season 4 is currently streaming on Amazon. It has already been renewed for a fifth season, which will premiere at an unknown date.

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