It’s easy to dispense with the usual formalities with Jeannette Walls. Even upon first meeting, Walls, 53, feels like an old friend. Our interaction is not so much a formal interview, but, rather, a lively conversation about her new novel, The Silver Star (Scribner, June).

Eight years ago, Walls wrote The Glass Castle (Scribner, 2005), a no-holds-barred memoir about her unconventional family. In it, she describes a hardscrabble childhood, during which her poverty-stricken parents evaded creditors by compulsively moving to different towns around the West and Southwest, before migrating east to West Virginia when Walls was 10. There, Walls’s mother and father and their four children lived in a three-room shack without plumbing or heat. While her father eventually descended into alcoholism and her mother became homeless by choice, Walls went on to achieve success as a writer and journalist. She graduated from Barnard College in 1984 and became a celebrity gossip reporter, first for various high-profile publications and then for MSNBC. A full-time writer now, Walls lives in central Virginia with her husband, the writer John Taylor.

Not only did The Glass Castle become a bestseller with four million copies currently in print, it spawned a trend that’s still going strong: tell-all memoirs exposing dysfunctional familyies and difficult childhoods in intimate detail. “People were encouraged to talk about it,” Walls explains, adding, “They must’ve thought, ‘Well, if she could write about her wacky family, why should I keep quiet about mine?’ ”

About this new novel, she confides that she feels a little nervous. “The Silver Star is the first real fiction I’ve ever written. I believed I was completely incapable of making things up. This is the first time.”

While technically true, The Silver Star is actually Walls’s second novel. Her debut novel, Half Broke Horses (Scribner), published in 2009, was inspired by the life of her grandmother, Lily Casey Smith, who grew up on a horse ranch in West Texas, eventually became a cattle rancher in Arizona. She died when Walls was eight. Walls, who wanted to explore her mother’s formative years, based Half Broke Horses both upon her mother’s memories and upon the historical record. When the sources she consulted conflicted with her mother’s recollections, Walls says, she deferred to her mother.

“I toyed with calling it complete fiction, but that would have been overly coy. So much of it was truth,” Walls confesses of Half Broke Horses, which Scribner touted as a “true-life novel” during their marketing campaign.

Writing fiction versus writing nonfiction, Walls adds, is like “navigating on the open seas versus a river.” Warming to the topic, she speaks rapidly in her enthusiasm, explaining that with fiction writing, “everything is a choice; if the writing does not ring true, it’s not simply a matter of digging more deeply,” as she did previously as a journalist and as an author. Walls calls her first book, Dish: How Gossip Became the News and the News Became Just Another Show (Morrow, 2000), “a deep book about a shallow topic that didn’t work.”

“It’s not a process of remembering, but rather of imagining,” Walls says of writing fiction, disclosing that when she considered the dialogue between key characters in The Silver Star flat, she and Taylor would act out scenes before she revised it.

Walls recalls that Lisa Genova (Love Anthony) was once asked what was the best advice anyone had ever given her regarding writing, and Genova responded, “Take an acting class.” Walls says, “At first, I thought, that is the weirdest thing I’ve ever heard. In writing The Silver Star, however, I finally understood that advice. You have to get inside your characters’ heads, to make them sympathetic, believable, and not two-dimensional.”

Insisting repeatedly that she completely lacks creativity and imagination—a self-perception that, at one point, she admits “obsessing over”—Walls explains that the fiction she is drawn to is “close to nonfiction.” She cites Ernest Hemingway, who “would go out and experience things so he could write about them” and Betty Smith, whose novel, A Tree Grows in Brooklyn, demonstrated to her “how powerful a story could be” when she first read it as a 10-year-old.

Walls says that the purpose of reading and writing is “getting to these emotional truths, and feeling that emotional connection. That’s what it’s about for me, even when reading cookbooks. It’s all about storytelling.”

The Silver Star, set in 1970, is the tale of the two Holladay sisters—12-year-old Bean, pragmatic but also an idealist, and 15-year-old Liz, a free-spirited artist. Abandoned by their charismatic but mentally unstable mother, Bean and Liz board a Greyhound bus and travel cross-country from California to their mother’s childhood home in rural Virginia, where they are taken in by their reclusive Uncle Tinsley. Byler, a company town with a cotton mill that was once owned by the Holladay family, is a different world from California for the two sisters, not least because they don’t understand the unspoken social rules for two young women living in the smalltown South during that era. As a result of their naiveté, they press charges against Jerry Maddox, one of the most powerful men in Byler, after he cheats Liz out of money he owes her and subsequently tries to rape her when she confronts him.

Not only does The Silver Star introduce readers to the same kinds of characters they encountered in The Glass Castle, but Walls’s novel also explores themes similar to those in her memoir. Walls makes no secret of the fact that she has confronted such issues as mental illness and sexual abuse in her own life—she readily admits that she modeled Uncle Tinsley’s hoarding tendencies on her own mother’s hoarding, and that she’s known “several Jerry Maddoxes” who “find vulnerable people and circle them,” including a previous employer who sexually harassed her.

“You gotta stand up to the bullies,” Walls insists. “Sometimes it doesn’t turn out so well, and you suffer the consequences. But to not fight back sometimes would be worse. Bean doesn’t know when to shut up and not go after people who could destroy her,” Walls says, explaining that the title of the novel is a nod to those who do “the right thing,” and in so doing, sacrifice themselves to protect others.

Walls describes herself as “Bean-like,” as she, like her fictional protagonist, is a “little headstrong” and “a bit of a fighter.”

It’s yet another instance in which Walls obviously is writing what she knows. Describing herself as having been on “the receiving end of ‘mean girl’ things” in her youth, Walls laughs as she remembers her early days as a gossip writer at New York magazine, when “some very famous people” threatened her with lawsuits or even physical violence. “It just brought out the yard dog in me; I’d think, ‘Yeah, come on and fight!’ That’s the way I am; I can’t help it.”

Maintaining that she is “tapped out” after writing The Silver Star, Walls says she can’t imagine writing another book. But seconds later, she insists that she can’t imagine not writing another book.

“I don’t want to write something unless I really have something I think is worth saying,” Walls explains. She adds, “We can all learn things about ourselves and others by sharing our secrets. Everybody has a story; everybody has their demons; everybody has their psychodramas.”