Answer, Please Answer

Worlds of the Imperium (Unabridged): optional

Firegod

Leviathan Wakes: Book 1 of the Expanse (now a Prime Original series)

Quinquepedalian

Falling Torch

Down to Earth

Caliban's War: Book 2 of the Expanse (now a Prime Original series)

Metropolis

Infiltration: Most Valuable Bestseller eBooks

Biddy And the Silver Man

Rogue Moon

Nemesis Games: Book 5 of the Expanse (now a Prime Original series)

The Time Traders

Some Will Not Die

The Testaments: WINNER OF THE BOOKER PRIZE 2019

The Cosmic Junkman (Unabridged): optional

Who?