Florida, 1920. Miss Alice Dartle comes to the Casadaga Spiritualist Camp (a real place), to learn to use her gifts for good: she can make winning bets on horses, or the stock market, but does not want to become rich (at least, not that way), and she can "read" people and objects.
Of late, she has dreamt of fire, and a man in fireman's clothes.
In Ybor City, Florida, Tomás Cordero returned from fighting for the US in the Great War, to find his wife dead of the 'flu. More recently, mysterious fires have been happening around him...fires that seem to bear messages from his lost Evelyn. After consulting his priest, he decides to consult Casadaga and, in particular, Alice Dartle.
Spoiler: It isn't Evelyn setting the fires. It's something much, much worse.
Told in alternating first-person PoV between Alice and Tomás, _Brimstone_ moves at a gentle pace that quickly moves to rollercoastery speeds and twists and turns. Both PoV charcters are likeable, human people, vulnerable without being weak, good without being syrupy.
My only complaint is with some of Priest's diction. I have complained about this in some of her previous works set in the past; she sometimes slips up and uses terms that fit fine in our mouths but stick out like sore thumbs when put in, say, Alice Dartle's (the one that particularly grated on me was "take it down a notch," but there were others). I blame her editors as much as her for this (in this case Anne Sowards of ACE books); it's hard to catch one's own verbal hiccups, but that's what editors are _for_.
Despite these infelicities, _Brimstone_ is a tense, delicious tale. As always, I wait to see what Ms. Priest does next.