Unspooling long-held family secrets has become a specialty of Dani Shapiro’s. She has hosted the popular “Family Secrets” podcast for several years, and her five published memoirs have often explored suppressed knowledge within her own family. With “Signal Fires,” Shapiro returns to fiction for the first time in 15 years, but she has not strayed far in terms of subject matter. Her new novel probes the long-term cost of secrets, as viewed through the Wilfs, a nonobservant Jewish family in a New York suburb.

For those of us who have been shaped by the presence of Holocaust survivors in our families and communities, the prospect of a day in the near future without living witnesses to the Nazi era is haunting. But another sort of witnessing is also on the verge of disappearing: the memory of daily life in the multitude of historic Jewish communities forever destroyed by the Nazis.