Quick recap
Earth is reeling from the asteroid strikes, and Marco makes Ceres the capital of the Belt. Drummer, now out of the Free Navy, raids Marco's supply lines and ends up allying with Avasarala. In the final battle at the Ring, Naomi uses the ships' mass to wake the entities inside the gates, which swallow Marco and his fleet. Filip abandons his father and survives. Earth, Mars and the Belt form the Transport Union. Holden accepts the presidency, resigns and leaves Drummer in charge. On Laconia, young Cara flees with her brother, who came back from the dead.
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