The New York Times bestselling All Souls Trilogy, written by USC Dornsife College of Letters, Arts and Sciences Professor Deborah Harkness, ends with the publication of The Book of Life (Viking Adult) on July 15.

The series, which includes A Discovery of Witches (2011) and Shadow of Night (2013), follows the adventures of historian Diana Bishop, a witch with deep ties to Salem, and Matthew Clairmont, a geneticist and vampire. Their love story takes them around the globe — even through time — to uncover the mystery of an enchanted manuscript that may hold the secrets to the existence of all supernatural creatures.

It was strange finishing the trilogy. Suddenly, my house seemed very quiet!

Deborah Harkness

Can you give us a teaser of the final installment of the All Souls Trilogy?

Readers can look forward to revisiting the characters and places they’ve loved in the series, as well as some surprises and the tying up of the plot.

How did you feel about concluding the story? Did you worry about angering your fans if you ended it “wrong”?

It was strange finishing the trilogy. Suddenly, my house seemed very quiet! I’ve been living with the characters for five years, after all. As for the fans, I hope they enjoy it, of course. But I can’t write the story they want. I can only write the story that has to be written.

You have a very devoted fan base. What have been some of the creative ways that your most fervent fans have shared their appreciation for your books? What kind of reactions have you received from your students about the books?

Fans have made up Pinterest boards, spun yarn, made quilts, crafted soaps and perfumes, fashioned jewelry — you name it. They are indeed a creative bunch! My students are very respectful of the fact that they’re in my classroom to learn history. But I have more traffic in office hours from students who want to talk about writing fiction, adapting fiction to film and get books signed for their mom!

Have you brought any aspect of your trilogy to your teaching?

No, but there is a lot of my teaching in the trilogy. Students who do read the books tell me they laugh when they read about something in the book that was a subject of a lecture or discussion, like what life was like at the court of Elizabeth I, how science was practiced in Elizabethan London or John Dee’s interest in alchemy.

Readers have been enchanted by the love story between Diana Bishop and Matthew Clairmont. What did you enjoy most about devising their adventures and their romance? What will you miss most writing about them?

I enjoyed trying to make their relationship real. Both of them are crabby, opinionated academics. It’s not always smooth sailing when two smart people get together, but in fiction it often seems like it. As for what I will miss — everything!

What do you bring that is different to the craft of writing fiction as a historian, specifically of early modern Europe?

I’m not sure because I’ve never written fiction as anything but a historian. I do have a new appreciation for the difference between careful research of a subject and deep immersion. As a historian, I am deeply immersed in the early modern period. I know how early modern people thought and behaved. In writing the final book, I needed to do research on more modern subjects. As a historian, I know how to research. I was careful. But I don’t have a feeling for the period, and I got things wrong. Happily, I have very generous colleagues who helped to sort me out. I came away with an even greater appreciation for just how hard it is to be a good historian and how lucky our students are to learn from the very best here at USC.

Is there a broader message in your novels that you want readers to grasp?

Yes. That empathy is the most important power there is. Without it, we are doomed. With it, we can truly change the world.

Are any aspects of the storyline or characters autobiographical in any way?

Of course. You have to write what you know. So Matthew has my love of wine and Marcus my love of sports cars, Diana is a historian and Emily makes dishes from my recipe box. The Bishop house is based on a house I owned and another one I wished I owned. The list is long!

You spent time abroad researching the settings for your books. Can you tell us some of the places you visited and how they helped you to convey their atmosphere in your novels?

I visited Prague and Venice specifically for the trilogy. I’d studied both cities, but I knew that I couldn’t bring them to life like I had Oxford or London without visiting them. I also spent time in New Orleans. The most important place I visited, however, was the small village of St.-Arcons-d’Allier in the Auvergne region of south central France, which became my model for the village of Saint-Lucien, Matthew’s hometown.

Previously there was talk of developing your books into movies. What is the status of that plan? Any other venues for the series?

As often happens, the film option with Warner Bros. lapsed before they went into production. A team of talented, committed people worked very hard to bring the series to cinematic life, but it is a complicated story.

With the All Souls Trilogy completed, what is your next big project?

Spring semester 2015! I’ll be teaching a new seminar on public history, and I can’t wait.

Read an excerpt from The Book of Life. Visit deborahharkness.com for a full list of cities and dates from her book tour.

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