LILAC GIRLS by Martha Hall Kelly

Just finished reading this book & really enjoyed it. Below is the synopsis:

Inspired by the life of a real World War II heroine, this debut novel reveals

a story of love, redemption, and secrets that were hidden for decades.

New York socialite Caroline Ferriday has her hands full with her post

at the French consulate and a new love on the horizon. But Caroline’s

 world is forever changed when Hitler’s army invades Poland in

September 1939—and then sets its sights on France.

An ocean away from Caroline, Kasia Kuzmerick, a Polish teenager, s

enses her carefree youth disappearing as she is drawn deeper into her role

as courier for the underground resistance movement. In a tense atmosphere

 of watchful eyes and suspecting neighbors, one false move can have

dire consequences.

For the ambitious young German doctor, Herta Oberheuser, an ad

for a government medical position seems her ticket out of a desolate life.

Once hired, though, she finds herself trapped in a male-dominated

 realm of Nazi secrets and power.

The lives of these three women are set on a collision course when

the unthinkable happens and Kasia is sent to Ravensbrück, the notorious

Nazi concentration camp for women. Their stories cross continents—

from New York to Paris, Germany, and Poland—as Caroline and Kasia

strive to bring justice to those whom history has forgotten.