A couple of novelists known for their time-traveling abilities (or at least those of their characters) are making another kind of move in September—to graphic novels. Audrey Niffenegger's The Night Bookmobile will be published by Abrams, while Ballantine will release Diana Gabaldon's The Exile: An Outlander Graphic Novel.

Well-known novelists turning to the comics form is nothing new these days, but Niffenegger, author of the bestselling literary fantasies The Time Traveler's Wife and Her Fearful Symmetry, may be the first to draw as well as to write her comic. "It's easier for artists to become writers than vice versa," she says. "We're all trained to write, but a lot of us aren't getting any artistic training as kids." Niffenegger is no newcomer to the visual arts. She has degrees from the Art Institute of Chicago and Northwestern University, and she cofounded Columbia College Chicago Center for Book and Paper Arts, where she continues to teach. Her passion for books and the visual arts weaves through her novels and is central to The Night Bookmobile.

To follow Niffenegger's evolution as artist and writer is to be led through a fascinating—and unusual—imaginative world. "Because I'm a book artist, I tend to move among a lot of different ways of telling stories, using words and pictures, or both," she says.

Niffenegger recalls her undergraduate days at the Art Institute of Chicago: "It was a heyday of performance art. I was trying to bring images together with stories, but I didn't like the ephemeral nature of performance art. I was looking for a way to put it into more permanent form, and the obvious answer was bookmaking." She went on to create her own book arts major, cobbling together etching, letterpress arts, and bookbinding. "I liked being able to control all aspects of design and production," she says.

The first product of this "self-assembled curriculum" was The Adventuress, a "novel in pictures." Another novel in pictures called The Three Incestuous Sisters was made while getting her M.F.A. at Northwestern. Both books have since been published by Abrams.

Niffenegger was working on The Three Incestuous Sisters when the idea for her runaway hit, The Time Traveler's Wife, came to her, though it was not initially clear that the story she had in mind would be a novel. "I thought it would be a picture novel," she says now. "But I realized the time-jumping wouldn't work, so I thought it could be either a film or a novel in words." Niffenegger opted for the novel.

If that book began as a visual idea and then moved into words, The Night Bookmobile underwent the opposite transformation. When the Guardian asked Niffenegger if she'd do a serialized comic for the paper in 2008, she decided to adapt a short story she'd published in Zoetrope All Story in 2004. "I spent a lot of time thinking about comics and what the images and the text were doing," she says of the process of adapting The Night Bookmobile. "I sat down and thought about where the pictures could take over and the words could be removed, and how the balance could shift back and forth."

Niffenegger asked friends to play the roles of the characters, and she took photographs of them on the streets of Chicago, inside branches of the Chicago Public Library and the library's bookmobiles. Then she used the photographs as she drew the pages and panels of the comic. Her full-color pen and ink drawings evoke a melancholy nighttime city and the solitude of the main character, Alexandra.

Alexandra is a young woman when we first meet her. She comes upon a mysterious bookmobile on a Chicago street in the middle of the night that contains every book she's ever read. This includes her diary, her own copy of Anna Karenina, "fattened by repeated reading," and a copy of Gravity's Rainbow, which is blank after page 57, exactly the spot where she stopped reading, the page marked with a popsicle stick. Niffenegger admits that this is an accurate portrait of her own reading life. "A lot of the story comes out of my own relationship to books," she says. "I've never made any headway with Pynchon. I'm sort of ashamed of that, but it is what it is."

Aside from Niffenegger's actual literary preferences, The Night Bookmobile delves into what it means to spend one's life devoted to books. "I've given over such an enormous part of my life to making them, reading them, writing them.... They've taken over." While Niffenegger adds, "I'm fine with that, I don't mind at all," The Night Bookmobile explores the darker side of this devotion. Ultimately, Alexandra gives herself totally to her passion for reading, passing over from her life as a Chicago librarian into the celestial realm of the night bookmobile, whose pleasures call to her like the sirens of Greek mythology. Niffenegger's fans will recognize the dark fairy tale tone of the story, colored as it is with her very contemporary, punk-inflected imagination.

Meanwhile, historical romance novelist Diana Gabaldon, with her graphic novel, The Exile, is taking on the hordes of die-hard fans of her bestselling Outlander romance series, who have frequently produced their own images of the characters they know and love. The Outlander books consistently top bestseller lists: the seventh installment, Echo in the Bone, debuted at #2 on the New York Times list in June. The series tells the story of Claire, a 1940s war nurse, who travels back in time to 18th-century Scotland, where she becomes embroiled in clan warfare and a passionate romance with Jamie Fraser. The Exile tells the same story, but from Jamie's point of view, offering readers both a new look at the story and fresh subplots.

Gabaldon's novels require her doing a great deal of historical research. "I was a research professor before I wrote novels," she says. "So I decided to write a historical novel because, though I wasn't sure how to write a novel, I did know how to do research. I always start with simple stuff, like what do people wear, what's the geography like, and then later choose the historical events."

The Exile involved a different kind of research because Gabaldon had to provide visual aids for artist Hoang Nguyen. "I showed him pictures of what a tartan looks like, men and women's clothes, the outfits and kilts." She adds, "Every once in a while, I was able to turn Hoang loose, and he'd come up with fabulous, unexpected things." The result is a painterly and richly detailed visual story to go with Gabaldon's richly imagined world.

What Gabaldon really enjoys about the comics form is the way it makes possible a wider range of points of view. Her stories move frequently from one character's perspective to another's, and she explains this as both a literary choice and a mental characteristic. "I recently read a quiz in the paper about how to tell if you have ADHD," she says. "Some questions had to do with anger and the others had to do with sensory input: ‘Do you feel like there's eight televisions on in your head all the time?' things like that. Well, I answered ‘no' to all the anger questions but ‘yes' to all the multisensory questions." And in the graphic novel, she says, she gets to indulge that multisensory tendency. "You can turn on a dime with regard to point of view in a comic. If you do that in a novel you have to either have an omniscient narrator, which is so old-fashioned, or constantly signal changes in point of view. But in a graphic novel you have the visual component, so it's instantly clear who's doing and saying what. It can give a much more multifaceted way of telling a story."

Of seeing her writing turned into a comic, Gabaldon says, "It was very entertaining to see the artist's translation of the story." How does she think her fans will react to seeing drawings of the characters they've seen in their heads for so long? "I know every single reader will open the graphic novel and say, ‘That's not what he looks like!' " says Gabaldon. "But then three pages in they'll get into it."

Sasha Watson is a freelance writer covering comics and graphic novels for PW Comics Week. She is the author of Vidalia in Paris.