A biographer’s task is inherently difficult: how to write about a public figure’s life while rendering it in a way that’s honest, compelling, and respectful. In the case of Joan Didion, the very private, award-winning author and writer, the task is more fraught. The Last Love Song, Tracy Daugherty’s excellent biography, satisfies all of those conditions. It’s a thought-provoking look at Didion’s distinctly Western upbringing, her marriage to John Gregory Dunne and the family they built, as well as a cultural history of the last half-century of American life. Thanks to Daugherty’s prolific, wide-ranging research and analysis of everything Didion has written that’s publicly available, we learn quite a bit about Didion and ourselves from this book.

Given the tragedies that Didion has endured over the last decade (the loss of her husband and her daughter, Quintana Roo), people in her inner circle these days are respectful of her feelings and didn’t want to participate in the project. Didion also chose not to participate. Daugherty, a professor of English and creative writing at Oregon State University, adopted Didion-esque methods. He examined the text, turning a very close eye on all of her published work, her many correspondences, and the many interviews she’s given over the years.

In photographs of Didion, she looks defiant, mysterious, glamorous, and fierce. She’s posed in front of her Corvette or she’s holding a cigarette in one hand and gazing confidently into the camera. These pictures—combined with Didion’s own habit of describing herself as unsure, groping her way through a journalism career—create a certain image. It’s an image of someone who ended up in journalism by accident but also led a glamorous life. As it turns out, that’s not the true story.

Didion was always an astute observer of the peculiarities of everyday life. From the beginning of her career, working at Vogue, she was simply taking assignments from the editors and doing her best to meet deadlines while navigating an unfamiliar urban landscape. She wasn’t conscious about voice and ideology; she was a very hard-working, diligent journalist. “Around the time of her second novel, Play It As It Lays, in the early ’70s, she began to gain more confidence and more of a sense of herself, that she did have a particular style and a particular voice,” Daugherty says. “But what’s important is that she still kept that notion of, ‘You know, I’m just a working writer.’ She never lost that pragmatic edge and it served her throughout her entire career.”

Daugherty notes one of Didion’s strengths: her ability to expose the fractures in the official stories that we tell about America. She locates people in faraway places and researches their weird, off-kilter movements in terms of the larger cultural forces at work in the 20^th century. He writes that Didion “sketches possible connections between seemingly disparate events: the Bay of Pigs, the Kennedy assassination, the coup in Chile, the Vietnam War, the worldwide heroin trade, the Watergate break-in, the Nixon resignation, the Iran-Contra affair, the cocaine blight in L.A., the rise of global terrorism.”

The book does have surprising moments. Despite Didion’s reputation for being shy and withdrawn, it turns out that she was quite social during her early years in Sacramento. “During her high school years she was involved in absolutely everything—all the clubs, the journalistic organizations, the glee club and the Spanish society,” says Daugherty. “The picture I got was a woman who was much more social than I would have thought, even at a very young age.”

Daugherty spoke with many people who knew Didion in her early years, including her first roommate, Rosa Rasiel, and Noel Parmentel, a mentor and suitor of Didion’s who ultimately introduced her to Dunne. However, The Last Love Song isn’t just a chronicle of Didion’s life choices, a look at how her writing style developed, or a behind-the-scenes glimpse of Hollywood during the time she and Dunne were screenwriters. It’s also biography as in-depth cultural history—and Daugherty has the perfect subject.

“Over 40 years she wrote about most of the important cultural changes that were taking place. I was also writing about those changes; but the challenge in doing that is that I was writing the individual’s story with the broader history,” says Daugherty, who has read Didion’s work for 40 years and also taught it for 20. “It’s easy to lose sight of the individual’s story. I had to rewrite sections of the book so I didn’t lose sight of the narrative about Didion,” he says. “She was a great model for that. It’s what she’s done in her own writing. It was both a challenge and a real education and she was a great teacher along the way.”

Christopher Carbone is a writer and editor based in the New York City area. You can learn more about him here.