Deep Night — Caroline Petit

From the author of The Fat Man's Daughter comes this novel of history, romance, and espionage starring “a compelling character” (Jacqueline Winspear).
 
Leah Kolbe, the daughter of a recently deceased British antiquities dealer, is having a romantic evening in Hong Kong when the chaos of a Japanese invasion erupts. She and her beloved Jonathan were planning a wedding, but now Leah escapes to Macao -- and Jonathan heads into battle.
 
As the Sino-Japanese war rages, Leah is recruited to go after a Japanese man in her capacity as a spy -- and to seduce him if she must. But as Jonathan goes missing, and then Pearl Harbor is attacked, Leah's mission, and her future, may change dramatically. . . .