For his new bloody epic, Ken Follett went back in time. Way, way back.

 The forecast was calling for rain, and this, for Ken Follett, was a problem. In two days’ time, he was slated to lead a busload of sleepy reporters on a crack-of-dawn field trip to Stonehenge, the setting of his new novel, “Circle of Days.” He had secured special permission to bring the group past the fence, before public visiting hours, so they could get up close. Umbrellas would spoil the shots.

“This is the kind of thing we do for most of my books, just because you, the media, demand good pictures,” he said during an interview over Zoom, adding, “I don’t know whether there’ll be any sun worshipers in our crowd of European journalists — I kind of doubt it, they’re a pretty material lot — but the stones really are awesome.”

The writer himself is not enthralled by what he called “the mystery of sunrise and sunset,” though he considers himself spiritual — a “lapsed atheist” who enjoys the occasional evensong. Follett had a strict Protestant upbringing. In his family’s home, there was no TV or radio; he was forbidden to attend concerts and sporting events or even join the Cub Scouts. But Follett was allowed to read freely, and did, gobbling up Shakespeare’s plays and James Bond novels. “It’s hard to think of a character whose life is more contrary to what the Plymouth Brethren believe in — the cigarettes, the cocktails, the women, the cars,” he said. “I remember saying to my father at some point, ‘What’s a martini?’” Growing up, he was often reminded: Our citizenship is not of this world.

But he was a worldly young man. At University College London, he studied philosophy and determined that the religious notions of his childhood did not withstand tests of logic; he also married for the first time, at age 18, and had two children. Afterward, he went into journalism, eager to learn about political events, and to interpret them, before anyone else. He also joined the Labour Party, where years later, in Farnham, he’d meet his second wife, Barbara. (In an email, she recalled that she did not find his “small, neat Poirot moustache” and immaculate beige suits and silk shirts “immediately appealing,” but that she was won over by his intellect and “fun-loving, try-anything attitude”; he gamely agreed to edit the local party’s monthly newsletter.) Once circumstances permitted, he became a literal champagne socialist — half a bottle each evening. No longer: “There came a point when I began to feel I was too old to drink alcohol every day,” said Follett, now 76, with snow-white, newscaster-thick hair.

He always aimed to be popular and worked hard at it. When his first novel was accepted by a publisher, his agent at the time encouraged him to use a pseudonym. Follett asked why, and she said, “Because in the future, you might want to write better books.” Early on he wrote up to three a year, often with different publishers and under different names, trying things out. In shop windows, he saw new books by Frederick Forsyth and Sidney Sheldon all heaped up, while a couple of lonely copies of his own works rattled around in the back. He asked himself: What do I have to do to move up?

And yet, after his breakthrough with the thriller “Eye of the Needle,” at age 29, he wasn’t satisfied. A lot of people could write one bestseller, he reasoned. And the second one — “Triple,” published in 1979 — could just coast on the reputation of the first. The third? “Then I thought, okay — I think I know how to do this, and I can probably do it for the rest of my life.”

Even today, Follett tests the market. He solicits notes on his outlines — writing nine for his smash hit “The Pillars of the Earth,” according to former agent Al Zuckerman — and circulates drafts among a dozen friends and relatives. “If somebody says, ‘Well, I got a bit bored in Chapter 3,’ that’s a very serious comment for me,” Follett said. “And that has to be dealt with.” For your Lee Childs, your Stephen Kings, your Folletts, these are table stakes: Millions will buy your book, just because your name’s on it. If one mind in 12 wanders off, that could be, what, half a million people you’ve bored?

“The Pillars of the Earth,” about the construction of a 12th-century cathedral, was not initially a success when it came out in 1989. Now it’s considered a British national treasure, an Oprah pick adapted into two musicals (one Spanish, one Danish), several board games and a TV series produced by Ridley Scott, in which Follett had a bit part as a medieval merchant. “Pillars” is a first-line-of-the-obit type book. And because of it, though his nearly 40 novels also feature human cloning and nuclear war and gizmos that cause earthquakes, Follett is far and away best known as a writer of period epics — set in old, older and now oldest England.

About Stonehenge, he does not wax poetic. It may be a wonder of the world, but “one of the weird things about it is that for a long time it wasn’t looked at with any seriousness,” he said. As a boy, Follett remembers, his family road-tripped there and he got to sit on the stones. Later, when Barbara was minister for culture, tourism and the creative industries from 2008 to 2009, she worked to convert it into a proper public site, complete with exhibition hall and discreetly sited parking lot. Though Follett was of course interested in her work — which involved bringing together all the relevant parties, including representatives of the druids — the monument itself held little allure.

But when he came across “How to Build Stonehenge,” by archaeologist Mike Pitts, his first thought was, That sounds like a Ken Follett book. He’d written about the building of a church, and then the building of a bridge, so why not Stonehenge, that Neolithic moonshot from thousands of years ago?

Reading a Follett epic is like watching early “Game of Thrones” — just as violent but somehow more earnest. It’s also like playing a Civ game, managing resources in a gussied-up spreadsheet: Establish your settlement, trade sheaves of wheat for bales of wool, and boom, you’ve got yourself a market town. Those resources are scarce. Life back then, whether “back then” is 500 years ago or 5,000, was nasty, brutish and short. Craftsmen, entrepreneurs and mystics emerge as heroes — those rare visionaries who can see past their next meal and imagine something more.

“Circle of Days” contains all the familiar pleasures of “Pillars.” Instead of valiant Tom Builder, there’s Seft, a gifted flint miner. For the villain, we’ve swapped out minor lord William Hamleigh for Troon, a “Big Man” who leads a tribe of farmers against their rivals, the herders and hunter-gatherers. There aren’t bishops, but priestesses, their authority deriving from their command of nature rituals and — this is crucial — basic arithmetic. (This is essentially a superpower in a world where those who can count do so using their fingers and toes. Confronted with the concept of “one thousand,” Seft complains: “I don’t understand these priestess numbers.”) As in the older novel, there’s even a scene in which a desperate man holds a newborn to the corpse of its mother, to breastfeed. The most common cause of death is cow-trampling.

The age of cathedral-building has been so extensively studied that, when writing “The Pillars of the Earth,” Follett said, “I’m not sure there was anything where I just had to make it up.” The prehistoric era required more invention, which felt more like deduction. Research took the form of long drives around Salisbury, as he tried to internalize the geography and imagine the movements of all these people across the plain. How did they live? What would they call themselves? What could convince them to divert their precious time away from tending cattle, sowing wheat, gathering hazelnuts and toward the ludicrous project of hauling these massive rocks into a perfect ring?

Follett’s prose has always been direct, but here the plainness feels extreme, reduced to the simplest elements. Across 688 pages, I could tote up, using just my two hands, the metaphors and similes. One man is said to have a face “like war”; a woman has hair that shakes like a leaf. Coming across these lines, I savored them like a hunter-gatherer would the marrow from a neglected bone. Was this shift in his style on purpose? He almost seemed startled by the notion. “I’ve got to have another look at some of my older books now.” He told me what a friend once told him: “You don’t do fancy writing — until you do.”

He has often described working on his first hit, “Eye of the Needle,” as being “like running downhill.” That never happened again, he told me: “That kind of luck never lasts long.” You learn not to depend on it. If you’re serious, if this is your career, then writing a novel is perhaps more like pacing the plain, scouting for stone. With great effort, those immense slabs slot into place.