Ultima is the sequel to Proxima and is the last book in the series. There was a climax midway in Ultima that would have been perfect to kick off a third book, but nup, the book just went on. I really respect that, many authors like to stretch a concept into an entire trilogy.
If you’ve read much of Stephen Baxter’s other works you’ll recognise many of the concepts at play in Ultima. A hubristic artificial intelligence is running around being sinister, there are alternate histories, a massive apocalyptic war with China and enigmatic god-like aliens. At times the book has the feel of a greatest hits album.
Proxima was about an abortive attempt to colonise a distant planet. The mission was made possible by mysterious wormholes, called Hatches. Ultima sees the colony’s survivors and their associates knock around a few universes in an attempt to discover the motives of the mysterious aliens. Along the way they must deal with anachronistic civilizations and a disturbingly single-minded AI.
The key phrase to describe much of the book’s setting is ‘Romans in Space.’ Baxter writes a fairly detailed, though not entirely convincing, account of how invading Germany allowed the Roman empire to survive and eventually develop a space program. Bombastic alternate histories like this are always a great deal of fun, so a lack of credibility isn’t much of a problem for me.
My favourite character in the book was ColU, a robot built to aid the colonising effort. In Proxima I interpreted him to be little more than a K9 knockoff, complete with the tinny voice. As the colonising effort breaks down he is forced to cannibalise his fellow robots and raise a child. He goes so far as to create a doll called Mister Sticks, who becomes a sweet running gag through the series. By the start of Ultima he’s reduced to his most basic circuits, and is carried on the back of a Chinese slave. ColU eventually becomes the moral center of the book and attains a dignity that few other characters can match. At one point he even stands up to an increasingly unreasonable AI. ColU’s convincing character growth is the reason he’s now one of my favourite robotic characters in fiction.
While I enjoyed the Proxima-Ultima series, I think that Stephen Baxter has written better books. I’d recommend his The Time Ships and the Manifold Sequence over this. And remember, if you do decide to read Ultima, read the prequel first.