The sixth book in New York Times best-selling Seanan McGuire's witty urban fantasy InCryptid series about a family of cryptozoologists who act as a buffer between humans and the magical creatures living in secret around us.

"The only thing more fun than an October Daye book is an InCryptid book." (Charlaine Harris, number-one New York Times best-selling author of Sookie Stackhouse series)

Improbable, adjective:

1. Not very likely to happen; not probable.
2. Probably not a very good idea anyway.
3. See also "bad plan".

Annie's expectations keep getting shattered. She didn't expect Verity to declare war on the Covenant of St. George on live television. She didn't expect the Covenant to take her sister's threat seriously. And she definitely didn't expect to be packed off to London to infiltrate the Covenant from the inside...but as the only Price in her generation without a strong resemblance to the rest of the family, she's the perfect choice to play spy. They need to know what's coming. Their lives may depend on it.

But Annie has some secrets of her own, like the fact that she's started setting things on fire when she touches them, and has no idea how to control it. Now she's headed halfway around the world, into the den of the enemy, where blowing her cover could get her killed. She's pretty sure things can't get much worse.

Antimony Price is about to learn just how wrong it's possible for one cryptozoologist to be.