Those of us who write about books are used to receiving press releases from publishers pointing out that the writer of the book being pitched has been working on said book for what seems like an unduly long time. An author has been writing the book for 12 years, the press release may brag; another release boasts about a seven-year gestation. The intent, of course, is to wow critics and readers with the awesome, epic undertaking the writer has accomplished. Then you read the book, and you think: What took you so long? That’s not necessarily because the book’s a stinker, though. When a publicist tees up a reader’s expectation by calling attention to how long it took to write the book, it’s difficult for a writer to live up to the hype.

So it’s refreshing to know that Robert Hilburn’s new biography, Johnny Cash: The Life, exacted a measly three and a half years of its author’s time. Hilburn was the chief music critic and pop music editor at the Los Angeles Times for more than three decades. Don’t let those three and a half years fool you, though: Hilburn first met Cash backstage in 1967.

Hilburn followed Cash’s career ever since that meeting, begging the Times to let him write about the musician’s 1968 Folsom Prison concert (Hilburn sensed that the man who sang “Folsom Prison Blues” would produce a memorable show there), even though he was just a freelance writer eager to get on staff at the newspaper. “We don’t want to give any space to that drug addict,” the editors told him (in 1965, Cash’s guilty mug had been splashed in hundreds of newspapers after he was caught with more than 1,000 amphetamines he bought in Ciudad Júarez, just across the border from El Paso). Hilburn pushed back and nabbed the assignment.

 Hilburn packed a lot into the three and a half years of researching and writing about Cash’s life. Johnny Cash will be the definitive bio of the tortured, truculent but often generous singer. Hilburn patiently wades through Cash’s many bouts with pills and alcohol, profiling those nearest Cash about the mental and physical effects of his addiction (this book features a lot of cars overturned by Cash). He penetrates the heart of Cash’s artistry; Cash came of age at the intersection of country, rockabilly and burgeoning rock ’n’ roll at Sun Records in Memphis, Tenn.. The behind-the-scenes stories Hilburn unearths from those early days are engrossing for anyone interested in American roots music. Hilburn traveled to tiny Dyess, Ark., Cash’s cotton patch of a hometown, three times to fully sense what the singer’s upbringing was like.

 Cash didn’t appoint an authorized biographer, but Hilburn may as well be it. Several months before Cash died, Hilburn visited him and his wife, June Carter Cash, in Tennessee. “After June went to bed,” Hilburn recalls, “we stayed up and talked for a long time.” Cash was having trouble talking because of his asthma. “He kept saying, ‘I want people to know everything that happened in my life, all the stumbles, and that way they can see that I overcame them.’ ” Hilburn says. “Even if he found it difficult to tell some of the stuff, his own life was his greatest message.”

Claiborne Smith is the editor in chief of Kirkus Reviews.