Writing novels take a lot of planning, research, and work, no matter what the genre. To write a dual timeline novel means doubling all of that. Why? Because you’re writing two novels–or stories–set in two different time periods and possibly even in two different places.
My genealogy novels are dual timeline stories. In each, the two stories must connect to each other thematically or merge together in the end. I alternate chapters set in the past and present, twisting the stories together. This is fitting, because it reminds me of a double helix of DNA–two strands of DNA intertwined like a spiral staircase.
When I say the writing a dual timeline novel means doubling all the work, I can give an example. When I wrote Bohemia and Broken Hearts, I had to research WWII, concentration camps, and the Sudetenland for the past portion. I had to research the Czech Republic, the small village of Mala Moravka, dog breeds from that area, trains and transportation between Munich and Mala Moravka, etc. for the modern-day portion.
Then I had to create characters and fit them into their respective settings and time periods. I had to plan two complete plots and figure out how they would connect. Since the book was the fourth in the series, I already knew some of the characters pretty well, but for the characters in the past, I had to create brand new people and figure their personalities and how they would interact with each other.
Luckily, I love doing research. That made the writing fun. Writing a dual timeline novel is definitely harder than writing a single timeline novel, but the effort is worthwhile!