Hard Science Fiction

Caliban’s War by James S. A. Corey: The Expanse, book two

The protomolecule sits on Venus building something, and the solar system's three powers are arguing about it while somebody starts shooting over a moon that grows the food.

The verdict

Better than the first book and one of the best political thrillers the genre has produced.

Quick facts

Author
James S. A. Corey
First published
2012
Publisher
Orbit
Series
The Expanse, book two of nine
Best for
Politics with real consequences, and a war that starts for believable reasons
Skip it if
You have not read Leviathan Wakes, or you want a resolution in this volume

Caliban’s War is the second Expanse novel, published in 2012, and it is the one where the series stops being a mystery and becomes a war. The protomolecule has taken up residence on Venus, nobody knows what it is building, and the solar system’s three powers are arguing about it while somebody on Ganymede starts shooting.

The idea behind it

The first book was about a discovery. This one is about what happens to politics when a discovery refuses to explain itself. Earth, Mars and the Belt all want the same thing and none of them trusts the others to have it, so a single incident on a moon with a food supply becomes an excuse for everyone to start moving fleets.

Underneath the manoeuvring, the novel is about parents and children, which it handles better than the genre usually manages. Two of its four strands are people trying to protect a child, from opposite ends of the same problem, and neither of them has the whole picture.

The story, spoiler-light

Holden and the crew of the Rocinante are pulled into the search for a missing girl after a massacre on Ganymede, the agricultural moon that feeds the outer planets. A Martian marine is the only witness and cannot make anyone believe her. A botanist with no leverage at all is looking for his daughter. And on Earth, the UN’s most senior political operator is trying to stop a war she can see coming and cannot prevent.

Two things are worth knowing before you start. The four strands converge properly, which is more than the first book managed, and the novel is funnier than its predecessor: the political scenes on Earth are the best comic writing in the series. It also ends on a cliffhanger that the third book resolves, so plan accordingly.

What makes it science fiction

The physics is the foundation and the novel never cheats it. Travel takes weeks, gravity is thrust or spin, and a fight between ships is a fight about fuel and time. That constraint is what makes the political parts work, because distance is the reason the three powers cannot simply settle things by force.

The alien element is used sparingly and well. The protomolecule is not a monster and not a villain; it is a piece of engineering from something that has no interest in human beings at all, and the humans in this novel spend most of it arguing about a technology they cannot understand. That is the honest version of a first contact story.

Who should read it, and who should give it a miss

Read it if you enjoyed Leviathan Wakes, because this is a clear improvement: tighter, funnier and better at handling several viewpoints at once. It is also a good example of the thing the series does best, which is politics with real consequences.

Give it a miss if you have not read the first book, because it starts mid-argument. And if you want a resolution in this volume, you will not get one: the story this book sets up finishes in Abaddon’s Gate.

Where to start, and what to read next

Read Leviathan Wakes first. This is book two of nine and the series is one long story about the same system at the same moment, so the order is not optional.

The two to pick up next are Abaddon’s Gate, which resolves the story this novel sets up and closes the first arc, and Cibola Burn, which takes the series to a frontier setting and is where the consequences of both become someone else’s problem.

The rest of the sequence, for reference: Nemesis Games, Babylon’s Ashes, Persepolis Rising, Tiamat’s Wrath and Leviathan Falls complete the nine novels. There are also novellas and short stories collected in Memory’s Legion, which can be read between the main volumes.

The verdict

Better than the first book and one of the best political thrillers the genre has produced, with a war that starts for reasons you can actually believe. Read it for Avasarala.

Frequently asked questions

Do I need to read Leviathan Wakes first?

Yes. Caliban’s War assumes you know the crew and the situation, and it opens in the middle of both.

Does it end on a cliffhanger?

It ends mid-story, with the situation unresolved. Abaddon’s Gate picks it straight up, so the first three books read best as an arc.

Can it be read as a standalone?

Not really. The plot is self-contained enough to follow, but the relationships and the political situation all depend on the first book.

How many books are in The Expanse?

Nine novels, plus a collection of shorter fiction, and the television adaptation covers roughly the first six.

Where can I buy it?

It is available in paperback and as a Kindle edition, and the buy links for Amazon.com and Amazon.in are on this page.

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