Abaddon's Gate

This is the third book of the Expanse series, and things are getting serious. At the end of book 2 the weird things brewing within Venus launched out into space, and the consequences are felt in book 3. I can't say anything more without spoilering the first two and a half books, so here goes: Spoiler Alert for the first half of the Expanse series ahead!
The series makes the transition from interplanetary sci-fi to interstellar sci-fi here as the weird alien artifacts create a gate that connects to a strange bridging space that contains hundreds of gates to other star systems. Naturally humanity gets all fighty over control of this, and a mystery is revealed: who are the aliens that created all this, and where are they? The book touches on these mysteries while dealing with the unfolding conflict between various factions trying to control how humanity deals with the huge change that follows from having access to a thousand new planets. The same core characters are again central to the unfolding adventure, and it's starting to get a bit silly that they always happen to be in the right place at the right time, and never get killed when everyone around them is getting killed.