Jim Lehrer has done it again. The Newshour host has written an absorbing ride of a novel—his twentieth—a flight of fantasy called Super.

Lehrer’s latest book is a fast-paced murder mystery set on the luxurious Super Chief train, which brings together a dazzling collection of historical characters: Harry Truman, Clark Gable, and Claudette Colbert, along with a mysterious stowaway, several Hollywood plutocrats, con men, and a prominent journalist, all on a suspense-filled ride from Chicago to Los Angeles in the spring of 1956.

Creative writing “is part of my soul; so is the journalism,” Jim Lehrer says. “I think if I had to choose, clearly I would do my writing.... It’s just who I am.”

It is a voyage of nostalgia for the 75-year-old veteran journalist, who displays his love for trains and his native Midwest as he recreates the mid-century opulence of the real-life “Train of the Stars,” down to its impeccable service, sumptuous meals and well-appointed drawing rooms. Before the sleek silver bullet reaches its destination, one passenger is kicked off, two are dead, another overindulges in booze and broads, and a lowly railroad official assumes the role of supercop.

Although the novel is based on a real train, real towns, and real people, the plot is pure fiction.

“I needed a lot of help walking my wavy lines between the real world and the made up,” Lehrer told The Daily Beast. “Everybody will be confused—that’s what’s fun.”

What is true to life, he explained, is that Clark Gable and other movie stars really did ride the Super Chief train. Harry Truman was on it for at least one round trip and several people died en route during its heyday, but most of the characters are “made-up folks based on amalgamations of real people,” according to Lehrer, “the rest is a carefully crafted concoction.” He added, “when you get people on a train, it’s magic.”

Although this is Lehrer’s second book to deal with rail travel, his true passion is for busses. His father was a manager of a bus station in Kansas and Texas and Lehrer helped to pay for college by working as a ticket agent. The basement of his spacious Washington. D.C. home is crammed with historic bus memorabilia: more than 300 original porcelain signs and hundreds of driver caps, badges, and bus models. His farm in West Virginia houses his proudest possession and “ultimate toy”—a vintage 1946 clipper bus painted in the colors of his father’s company, which he drives around the rural backroads. “I’m an incurable collector,” he admitted.

He is also a workaholic who has anchored The Newshour on PBS for more than 30 years, moderated 11 presidential debates, and won innumerable Emmys, Peabodys, and other prestigious awards. Like his 20 novels, two memoirs, and three plays, his life is carefully scripted. To produce one book a year, he utilizes every spare minute on trains, planes, cars, in between meetings, early in the mornings and on weekends. “Whatever else I’m doing, I’m always working on a book,” he said. “It’s like a rubber band—I always snap back to it.”

Years of reporting have given him the unique ability to switch from an on-air conversation dealing with an international crisis to penning a grisly murder scene.

“It's a simple case of training, it's like riding a bicycle. I've been doing daily journalism for so long… and I can very easily move from one story to another. I can also move journalistically to my novel writing in the same way.… Turn on full speed, turn it off, and then turn on the other one. And now I've done it so often for so many years it's a natural way of life to me.”

In Super, there are a few delicately written sex scenes the prodigious author feels no compunction about writing. “I think sex is best left to the imagination, the more you can trigger the imagination, the more sensuous it is rather than graphic detail.” But Lehrer added, “I’m not squeamish about writing about it. If your characters are real to you they do real things and sometimes that includes sex.”

Lehrer is already well into his next book, a nonfictional look at presidential debates, due out in 2011. Meanwhile, his day job has undergone a makeover. To propel the Newshour into the digital age, it has gone back to its original two-anchor concept and Lehrer now takes Mondays off.

Even though he underwent an aortic valve replacement in 2008, he insists he has no intention of retiring anytime soon. “When I start drooling on the air, I'll know to stop,” he said.

As for his writing, “That is part of my soul, so is the journalism. I think if I had to choose, clearly I would do my writing because that gives me food for not only thought, but for everything. It's just who I am.

“When you make up a story like the Super Chief, that lives because I lived and I created it. The news that I do, I'm reporting things about other people and what they do, it's not a creation per se. The writing of fiction is what gives me great, great satisfaction.”

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Sandra McElwaine is a Washington-based journalist. She has been a reporter for The Washington Star, The Baltimore Sun, a correspondent for CNN and People, and Washington editor of Vogue and Cosmopolitan. She writes for The Daily Beast, The Washington Post, Time, and Forbes.