Affinity Konar’s harrowing novel invites us into the world of twin sisters Stasha and Pearl Zamorski, a world whose portal is a crowded journey in a cattle car, their coming days a trudge toward terror. The girls, at 12 years old, are delivered into the “care” of Nazi doctor Josef Men­gele and entered into his collection of genetic curiosities. Their delivery is perceived as a privilege, for the relative safety of their families has been promised. Of course, promises are often meant to be broken.

It’s easy to forget that the protagonists of this well-researched story are children, if in name only. Their measured and thoughtful narrative voices belie their youthfulness, raising the question: Could one possibly retain one’s innocence in a place like Auschwitz? Nevertheless, the children rely upon games to pass the time. They fashion creatures in the clouds during stolen glances at the sky. Their comprehension of the cruel “experiments” in which they are involved is questionable.

For instance, Stasha believes that she has been rendered deathless thanks to one of “Uncle” Mengele’s injections, a fanciful notion that disturbs more than it comforts. This childish idea eventually leads Stasha to a nuanced, wise-beyond-her-years observation: