To make a documentary, you must be passionate about the subject. But too much admiration can lead to a film with more of a fan's view than is good for it. Such is the case with "Gonzo: The Life and Work of Dr. Hunter S. Thompson."

Certainly there is a lot to admire about Thompson, a gifted writer who, along with Tom Wolfe and Gay Talese, is considered to be one of the founders of the style of writing called New Journalism, also known as creative non-fiction.

And "Gonzo," directed by Alex Gibney, is filled to the top with admiring celebrities -- including Wolfe, singer Jimmy Buffett, and politicians such as former president Jimmy Carter and presidential candidate George McGovern -- offering encomiums to Thompson's talent. Both of Thompson's wives appear on camera, as does his son, and Johnny Depp reads the narration and does a few on-screen riffs with Thompson's writings.

But Thompson was not just a writer. He created a hard-drinking, drug-ingesting persona for himself; as someone observes about his "Fear and Loathing in Las Vegas," he made being way out of control his topic. In the end, he became as much a prisoner of that facade as any square trapped in a nine-to-five job.

Gibney knows this and pays lip service to it, but the director of "Enron: The Smartest Guys in the Room" and "Taxi to the Dark Side" seems to have parked his skepticism at the door for this project. Instead of pushing for tough answers to difficult questions, this film is content to mythologize Thompson's bad-boy behavior, celebrating things like his willingness to drink a bottle of bourbon a day and go hunting with a submachine gun.

The most interesting parts of "Gonzo" are its explorations of Thompson's early days. We learn that he grew up in Louisville, Ky., the son of a librarian, and always felt like an outsider. We hear that he typed "The Great Gatsby" over and over again to teach himself to write and we watch an unnerving clip of his appearance on TV's "To Tell the Truth."

But too much time in this overly long film is spent on minutiae: Does anyone really care at this point how Thompson felt about Ed Muskie or Thomas Eagleton? And "Gonzo" would have benefited from some attempt to analyze why so much of our culture is fascinated by the reckless behavior that its subject epitomized. There's a bit of Thompson in George W. Bush, something neither his partisans nor the presidents want to acknowledge, but you'd never know it from this film.

kenneth.turan@latimes.com

"Gonzo: The Life and Work of Dr. Hunter S. Thompson." Unrated. Running time: 1 hour, 58 minutes. In limited release.