The Ten Thousand Doors of January, by Alix E. Harrow

Review copy provided by the publisher.

For a long time you couldn't get a portal fantasy for love nor money, most particularly not for money, as I'm pretty sure the fanfic ones were out there for love. But for several years, portal fantasies were out of fashion for adults. They seem to have come back in the last few years, but in a self-aware, self-examining iteration.

The Ten Thousand Doors of January is one instantiation of that. It is full of portals--the title is no exaggeration--but almost all the action takes place in this world, or a version of it. January Scaller has spent her entire childhood puzzling over various mysteries of her existence--when her father will make one of his brief returns from his assorted travels, for example, or what happened with the mysterious and magical door she found in Tennessee as a child, what the coin she picked up beyond it meant. The other people she meets are her guardian's house are varied in age, race, expertise, but none of them seems ready to answer her questions.

And then as January comes closer to coming of age, everything seems to happen all at once. Her guardian tells her that her father is dead, that she must adjust to a new role in the world--and all of the things that she has hoped and known about her guardian shift out from under her. The world opens up new possibilities, many of them terrifying--many of them worlds themselves. And her own power and control are simultaneously beyond what she dreamed and woefully inadequate for the task at hand.

So it's a good thing she's made some loyal friends along the way.