Ghost Talkers by Mary Robinette Kowal

“It was the idea of it that got me into the book, and Kowal’s affectless presentation of the mediums and their work that kept me going. Did it help that the main plot concerns American heiress Ginger Stuyvesant (a working medium, exhausted and burnt-out by the stresses of experiencing the deaths of hundreds of young men) and her fiancé, British intelligence agent Benjamin Hartford? Of course it did. I like a good spy story as much as anyone (even without spaceships). And once things get going, Ghost Talkers has a good thrust with the Germans trying to discover the location of the Spirit Corps, a highly-placed mole in the British command, secret murderers, double crosses, codes and ciphers.

But it was that rare ability of Kowal’s to make what could have been a completely goofy add-on to the British war effort into something that felt completely wedded and solid that sold me — that spark of a great idea, well-executed. It is a story that just works. That lays out a presumption (ghosts are real), builds a plot architecture around it (they might be useful intelligence assets), and then grounds it with emotional weight (those forced to talk to the ghosts of the young and dead might not come out of it unscathed).” — NPR Books