In this utterly gripping thriller, Sarah, the fearless heroine of indie bestseller Orphan Monster Spy, hunts a rogue German doctor in Central Africa who might be a serial murderer.

It’s 1940, and Sarah Goldstein is hiding in plain sight as Ursula Haller, the Shirley Temple of Nazi high society. She helps the resistance by spying on Nazi generals at cocktail parties in Berlin, but she yearns to do more. Then the spy she works for, the Captain, gets word of a German doctor who’s gone rogue in Central Africa. Rumors say the doctor is experimenting with a weapon of germ warfare so deadly it could wipe out entire cities. It’s up to the Captain and Sarah to reach the doctor and seize this weapon–known as “the Bleeding”–before the Nazis can use it to murder thousands. Joining them on their journey, in of the guise of a servant, is Clementine, a half-German, half-Senegalese girl, whose wit and ferocity are a perfect match for Sarah’s. As they travel through the areas now known as the Republic of the Congo and Gabon, Clementine’s astute observations force Sarah to face a hard truth: that mass extermination didn’t start with the Nazis.

This unbearably high-stakes thriller pushes Sarah to face the worst that humanity is capable of–and challenges her to find reasons to keep fighting.

Her name is Sarah. She’s blonde, blue-eyed, and Jewish in 1939 Germany. And her act of resistance is about to change the world.

After her mother is shot at a checkpoint, fifteen-year-old Sarah meets a mysterious man with an ambiguous accent, a suspiciously bare apartment, and a lockbox full of weapons. He’s part of the secret resistance against the Third Reich, and he needs Sarah to hide in plain sight at a school for the daughters of top Nazi brass, posing as one of them. If she can befriend the daughter of a key scientist and get invited to her house, she might be able to steal the blueprints to a bomb that could destroy the cities of Western Europe. Nothing could prepare Sarah for her cutthroat schoolmates, and soon she finds herself in a battle for survival unlike any she’d ever imagined. But anyone who underestimates this innocent-seeming girl does so at their peril. She may look sweet, but she’s the Nazis’ worst nightmare.