'Middlegame' is a standalone novel from Seanan McGuire, author of the 'Wayward Children' series, among others that is ambitious, cool, and hard to put down. It involves a conspiracy of alchemists fighting over the soul of the United States. There is a theory about a Doctrine that is the underlying and unifying fabric of not only the nation, but all of creation. For years alchemists have tried to gain control of aspects of creation by embodying abstract concepts into created children. The greatest triumph, of course, would be to personify the Doctrine itself, and one James Reed might have done it
The novel, involving as it does shaking the foundations of everything, follows an occasionally non-linear time-line. After the first few shifts I got used to the structure. There are two, perhaps three, main characters. Twins Roger and Dodger were conceived to be pawns in Reed's bid for power. They've been raised apart as "normal" children, but are intrinsically connected. Language is Roger's domain and Dodger has math. They are incredibly gifted from a young age, but have very real weaknesses. They are only complete when together. The book begins with blood and the knowledge that the two of them have a long battle ahead of them.
An aspect of Roger and Dodger's connection is the ability to "reset" their timelines, the catch is that they can't remember what happened after the point they return to and might end up making the same mistakes. Over and over. A third character, Erin, has her own dark history and is more aware than most about the loops in time.
I said this book was ambitious, and it is, tying in historical figures, geography, and of course math and literature. As addictive as it was, there were some elements of the plot that were hinted at, but were never addressed. With so much going right in this book, I'd say it doesn't really matter. This book exceeded my expectations, which were pretty high.