Read­ers famil­iar with my pre­vi­ous books may know that my inter­est in sto­ries set dur­ing the Sec­ond World War comes from the years I spent liv­ing in Poland among Holo­caust sur­vivors, work­ing on issues relat­ed to that era. How­ev­er, some may be sur­prised to learn that I do not write about the sur­vivors I met, nor about the sto­ries they shared. While I derive inspi­ra­tion from these sto­ries, they sim­ply aren’t mine to write.

I’m often asked how I find ideas for my books. The short answer is that I go look­ing for them. But then the ques­tion becomes, how do I know when I have found it?

It comes down to some­thing I call The Gasp. If I find a bit of his­to­ry that is so untold and orig­i­nal that it caus­es me to gasp after a quar­ter cen­tu­ry of work­ing with the war, I’m hope­ful that read­ers will react the same way.

In the case of Code Name Sap­phire, The Gasp hap­pened when I learned the true sto­ry of the mis­sion to lib­er­ate pris­on­ers from a train head­ed for Auschwitz. I was stunned — and I had so many ques­tions. On the one hand, I won­dered: how could peo­ple be so brave as to under­take such an unthink­able and dan­ger­ous attempt? But on the oth­er hand, I want­ed to know why more peo­ple had not tried to do the same thing for the count­less vic­tims that were being trans­port­ed across Europe to the con­cen­tra­tion camps. I decid­ed that I want­ed to write a nov­el about both the sabo­teurs and the peo­ple they sought to rescue.

I began by research­ing the actu­al train that was lib­er­at­ed. One of my best resources was The Twen­ti­eth Train: The True Sto­ry of The Ambush of the Death Train to Auschwitz by Mar­i­on Schreiber. It taught me about the actu­al res­cuers, three men (a Jew­ish doc­tor and his two non-Jew­ish friends) from the Jew­ish Defense Com­mit­tee who under­took the res­cue large­ly on their own. (Sup­port for the mis­sion had always been ten­u­ous, as some resis­tance lead­ers wor­ried that the res­cue would impede their prin­ci­pal goal of fight­ing the Ger­mans. Their sup­port fur­ther waned when the Ger­mans switched from third-class rail cars to cat­tle cars, which the resis­tance feared would ren­der the already treach­er­ous lib­er­a­tion impos­si­ble.) I also dis­cov­ered how the res­cuers worked with pris­on­ers inside the camp, pro­vid­ing them with tools to aid in their escape and mon­ey for after they were freed.

In research­ing, I found out that, trag­i­cal­ly, the lib­er­a­tion was of mixed suc­cess: some pris­on­ers made it off the train, but oth­ers were recap­tured or died try­ing to escape. The three res­cuers were arrest­ed and impris­oned; one was exe­cut­ed. Nev­er­the­less, the mis­sion was impor­tant, and it undoubt­ed­ly gave count­less oth­ers the hope they need­ed to escape or sim­ply survive.

The main char­ac­ters in Code Name Sap­phire—Lily, Nik, and their son, Geor­gi — are a fic­tion­al fam­i­ly. But I want­ed them to embody the spir­it of the real pris­on­ers, par­ents and chil­dren, med­ical pro­fes­sion­als, and intel­lec­tu­als who lived dur­ing the war. Although the three prin­ci­pal res­cuers were in fact men, I decid­ed in my sto­ry to make one of them, Han­nah, a Jew­ish woman, work­ing in col­lab­o­ra­tion with oth­er arms of the Bel­gian resis­tance. So many sto­ries of women have been lost to a his­to­ry that ignored them; who’s to say what women might have done behind the scenes? I also sought, through the char­ac­ter of Sofia, to rec­og­nize the plight of the Roma com­mu­ni­ty dur­ing the Holo­caust, which so often goes unnoticed.

I chose to inter­weave the sto­ry of the train res­cue with anoth­er remark­able aspect of the war: the escape lines through­out Bel­gium, Hol­land, and France, and the heroes and hero­ines who brave­ly spir­it­ed Allied air­men out of Europe. My ren­der­ing was prin­ci­pal­ly inspired by The Comet Line, a Bel­gian net­work that relied on the assis­tance of approx­i­mate­ly three thou­sand civil­ians to help approx­i­mate­ly 775 Allied air­men escape Occu­pied Europe. Some esti­mate that as many as sev­en­ty per­cent of those work­ing with The Comet Line were women, many of whom sac­ri­ficed their lives in the process. Excel­lent accounts of these real-life escape routes and the self­less peo­ple who ran them can be found in The Free­dom Line: The Brave Men and Women Who Res­cued Allied Air­men from the Nazis Dur­ing World War II by Peter Eisen­er and Lit­tle Cyclone by Airey Neave.

I also learned much about the Jews of Bel­gium, both about those who already held cit­i­zen­ship and those who had immi­grat­ed from oth­er coun­tries. Through my research, I bore aston­ished wit­ness to their jour­ney from the ear­li­est days of occu­pa­tion, to their intern­ment and bru­tal treat­ment in camps such as Breen­donk and Meche­len, to, in many cas­es, their ulti­mate depor­ta­tion. If you would like to learn more about this his­to­ry, I rec­om­mend The Pris­on­ers Of Breen­donk: Per­son­al His­to­ries from a World War II Con­cen­tra­tion Camp by James M. Deem.

Code Name Sap­phire is my twelfth book. My com­mit­ment to illu­mi­nat­ing impor­tant pieces of his­to­ry through sto­ry­telling is stronger than ever. I con­sid­er my books to be, first and fore­most, love songs to the peo­ple who lived in those most extra­or­di­nary times. I hope that read­ers will be as moved as I have been — and that they will long remem­ber both the char­ac­ters who inhab­it my sto­ry and the real peo­ple who inspired them.