Part two of the topnotch space opera begun with Leviathan Wakes (2011), from Corey (aka Daniel Abraham and Ty Franck).
Previously, a dangerous alien protomolecule was weaponized by an amoral corporation and field-tested against a habitat in the asteroid belt, bringing Earth, Mars and the Belt to the brink of war. Thanks to whistle-blowing Belter spaceship captain Jim Holden, all-out war was averted and the habitat diverted to Venus. Now, the protomolecule has taken over that planet and appears to be building a gigantic, incomprehensible device, a development viewed with alarm by the great powers. Then, on Ganymede, a creature able to survive unprotected in a vacuum, immune to most weapons and hideously strong, wipes out several platoons of marines. Fighting breaks out and the great powers teeter on the brink of war. Mysteriously, just before the monster's appearance, somebody kidnapped a number of children who all suffered from the same disease of the immune system. Botanist Prax Meng, the father of one of the children, asks for Holden's help in finding his daughter. As Ganymede's fragile ecosystem collapses, Holden flees with Prax. Meanwhile, on Earth, fiery old U.N. bigwig Chrisjen Avasarala realizes she's been outmaneuvered by forces in league with the corporation that thinks to control the protomolecule. The characters, many familiar from before, grow as the story expands; tension mounts, action explodes and pages turn relentlessly.
Independently intelligible but best appreciated after volume one—and with a huge surprise twist in the last sentence.