Leviathan Falls

The final novel in The Expanse series.

Set in the distant future in an inhabited solar system split between three major factions (Earth, Mars, and the Asteroid Belt / Outer planets), Leviathan Wakes follows the crew of an ice hauler — captain James Holden, XO Naomi Nagata, pilot Alex Kamal, and engineer Amos Burton — after they encounter a ship in distress. A private company unleashes an alien substance known as the Protomolecule, plunging the system’s various factions into a major conflict as they vie for power.

The substance is essentially a technology that can replicate itself and manipulate matter, and it eventually links our solar system to a vast network of other gates and habitable planets, allowing humanity to expand into the galaxy. In the latest pair of novels, Abraham and Franck jump decades into the future, where a lost Martian task force returns — having used the Protomolecule to create some advanced technologies and set up a fascist civilization — and are bent on creating an interstellar empire.