“You have this group of characters and you write 100,000 words about them, but you haven’t finished you have to keep making up more and more stuff about them. “Certainly it’s easier to write a 100,000-word thriller than it is to write one of these bigger novels, which are three times as long and 10 times as difficult,” Follett says in a phone interview from his home in London.

18 - takes on the rise of Nazi Germany, World War II, the dawn of the atomic age and the beginnings of the Cold War. The second, a 940-page doorstop of a book called “ Winter of the World” (Dutton, $36) - to be published Sept. The first volume, the bestselling “ Fall of Giants” (2010), encompassed World War I, the Russian Revolution and the struggle for women’s suffrage. Now Follett is amid his most audaciously ambitious project yet: the Century Trilogy, in which five interrelated families - American, Russian, German, English and Welsh - battle through the most dramatic events of the 20th century in a story that will sprawl over nearly 3,000 pages. At 63, the Welsh author is one of the last Mohicans of the form, having traded his highly successful thrillers (“ Eye of the Needle,” “ The Key to Rebecca”) for the multigenerational historical saga in 1989’s “ The Pillars of the Earth” (adapted as a Starz miniseries in 2010) and its sequel, 2007’s “ World Without End,” which premieres as a miniseries on Reelz next month. Who wants to spend so much time, day in and day out, with the same set of protagonists? Who wants to do all that research? Who has the nerve, not to mention the patience, to keep all those narrative balls in the air over hundreds of pages?

In recent years, however, the form has fallen somewhat out of favor with writers, if not with readers. Tolstoy largely invented the form in 1869 with “ War and Peace,” and by the middle of the 20th century, its latter-day stalwarts - including James Jones, Herman Wouk and the tireless fiction factory known as James Michener - bestrode the bestseller lists like the titans they were.

Well before blockbuster movies, there were blockbuster novels: big, juicy, page-turning epics, with dozens of characters, exotic settings and multiple plots playing out over several years, often against the backdrop of some extended historical conflict.

Ken follett century trilogy books