Ultima

Stephen Baxter's Proxima was one of the great science fiction novels of 2013. It told of a group of convicts who are shipped out to the newly discovered world of Proxima IV, where the reluctant and quarrelsome settlers make a strange discovery: hatches which open to other possibilities. Now, in the sequel, the stage becomes even bigger. We start on an Earth still ruled by the Roman Empire, but an empire that has now reached the stage of space exploration. But from here the hatches start to open up new worlds, new universes, and a plan that seems to stretch from the beginning of time through to its very end. Why it's on the list: Baxter has always been at his best when playing with big ideas, and they don't come much bigger than this.