Be My Enemy opens with a précis of the start of Planesrunner (2011), the opening book in the Everness series. Except that it becomes more confusing as it goes on, conflicting with recollections of the first book until it cracks open and demonstrates just what the many worlds theory really means. The Everness series may be aimed at a younger reader than McDonald's Brasyl (2007) but it is a thematic sequel and, to my mind, delivers the narrative punch of quantum possibilities better than that novel did.
Everett Singh, as readers of the first book will recall, is a genius. This is pretty much necessary when your genius father has given you the only known "map" of all the many worlds at the moment that he is captured by unknown forces. That his captors, the Order, appear to control the only gate out of our Earth to the other nine worlds of the Plenitude would appear to give them the absolute upper hand. That they speak of a fight against "forces beyond the Known Worlds more powerful and dangerous than you can imagine" (p. 31) suggests that any right-thinking person would help them. However, Everett immediately rebels against their methods and runs. He finds support in the crew of the airship Everness and he has the Infundibulum—that map of all worlds—and a jump gun which can move the airship between worlds. His mission, though, remains the same—to find his father and rescue his family, despite ever-increasing peril.
That mission is made much the harder by the continuing efforts of the Order to capture the Infundibulum (which resides in Everett's tablet computer). They fetch another version of Everett, one so similar to our protagonist that even his password is the same "complex string of numbers and letters, upper case and lower, that no one but he could even begin to remember" (p. 71) but who is not quite our Everett. Everett M's father is dead and, manipulated by Charles and Charlotte Villiers (versions of the same person from different worlds) he does what he sees as necessary to protect his mother and sister, even at the cost of his alternate self. Everett M is also upgraded to superhuman powers using the technology of the alien Thryn who have made contact with Earth 4.
A self-replicating alien technology which humanity has decided is not self aware? There is deep strangeness available here as McDonald has an infinity of worlds (well 1080 anyway) to select from. The challenge in this story is to both demonstrate and constrain the possibilities available in a coherent form. This book does both, showing more of these possibilities than the first in the series, but maintaining a through line for the primary characters and the threats facing them. The main mechanism McDonald uses for this is the core theme of science. McDonald provides multiple snippets of scientific knowledge—a brief explanation of simple harmonic motion as Everett swings from the end of a power cable, a description of entropy—alongside repeated reinforcement of the validity and meaningfulness of scientific method.
[W]hat I believe about reality is not built of sand. It tests itself against reality at every point, and where it is weak, where it can be undermined, it makes itself stronger. The universe is rational, even when it seems that it is not. (p. 204)
Balanced with this is character. As the same page lays out:
There are rules. But then, Everett thought, there are people. People don't obey the rules. . . . You see what you want to see. We make our own luck here.
Everett M is somehow less lucky. He is so much like the first that it seems he must buck the manipulations of Charlotte Villiers to team up with Everett, but McDonald's plotting is tougher than that. Less self-assured and gradually more twisted by the traumas he endures, Everett M is on the path to villainy. Still, having learned the character of the first Everett, it's hard to believe that Everett M could do the things he does. Perhaps, given that Everett endangers everyone around him through an act borne of anger, it is a demonstration of the limits of character in the face of impossible decisions.
There are other ways in which Everett M is not Everett's equal. The first few chapters of the book are balanced, alternating between Everett and Everett M, but after their first major showdown, Everett M fades from the main narrative. This feels odd, as a reading experience, as the book moves back to a solo focus on our primary protagonist until Everett M is allowed sub-chapters towards the end. In between, the book spends its time on Earth 1, building a picture of the most advanced of the human worlds—and the price they have paid for hubris. This makes for a hundred pages of post-apocalypse novel, even including a hunting scene which provides the moral "that if you kill something, then you must eat it" (p. 143), and a siege-bound society. McDonald seems almost at play here, showing just how much could be possible, but he soon draws us back to the struggles of our protagonist. There is never any doubt where the core of the novel lies. The recurring characters from the first book are lightly penciled in, but they don't appear to grow or change in the way the Everetts do. Late in the book, we are given a scene from the point of view of his friend Sen. This makes her more real, but also feels like a way to exclude the reader from the mind of the protagonist for a few moments.
All this is wrapped up in a pacy book filled with tropes McDonald takes from across the genre and makes his own, whether it is AI or nanotech, unpeopled Earths or post-apocalyptic worlds. The airship which is the series home has a real three dimensionality whilst the jump gun acts as pure plot device. In softer hands these books could become a "monster of the week" series but here there are consequences, none more so than when Everett is punched in the stomach by an authority figure. This basic, personal violence is a reminder that this is not a game and that even a genius can't get through unscathed. I can't wait to see what happens next.