Gripping, intelligent science-fiction from worldwide bestselling author Garth Nix. For fans of the Expanse series by James S A Corey including Leviathan Wakes, and David Weber's Honor Harrington books.

Caught me a mountain

Rode it to the stars

It's business as usual for Ship Leader Parnell Shi-Sawahla and the crew of the corvette Sassafras. Ride a Massif to a new system, fight the enemy, repeat. For more than two hundred years humans have been hitching rides on these sentient, starfaring mountain ranges, colonising planets and exporting an on-again, off-again war between Earth and Mars.

But the big questions are always there, behind every battle, every new colony, every new star system discovery.

Why do the Massifs carry humans to the stars?

Why do they help us export our wars?

What's in it for the Massifs?

Ship crews aren't supposed to ask these questions, they aren't supposed to think about these questions, and they definitely aren't supposed to go deep and talk to Massif avatars. But now Parnell and his tight-knit crew must try to find the answers, to save not only themselves but the future of humanity.