A Swashbuckler’s Paper Trail : A gripping biography of the steep trajectory of Errol Flynn lies in an unexpected place: a collection of his movie posters.

For decades, biographers have battled over the facts of a life that, in any telling, seemed too incredible to be true.

Was Warner Bros. action hero Errol Flynn a Nazi? A bisexual drug addict? Or merely the greatest adventure star the movies ever produced?

Lifelong Flynn buff Lawrence Bassoff can cite scripture from every book on the “Adventures of Robin Hood” star--from Charles Higham’s scandalous “Errol Flynn: The Untold Story” to Tony Thomas’ scholarly rebuttal, “Errol Flynn: The Spy Who Never Was.”

Now, after 20 years of work, it’s Bassoff’s turn to offer a look at the Australian-born movie icon--using a surprising set of evidence.

Bassoff’s new book, “Errol Flynn: The Movie Posters,” features 180 color reproductions of international movie posters, lobby cards and other artwork to follow Flynn from his early, inept film role in an Australian cheapie through his glory years as Hollywood’s most dashing--and notorious--leading man.

Most affectingly, the pictures create a portrait of Flynn’s last, alcohol-drenched decade of B-movies, aborted projects and semi-comebacks (he died at age 50 in 1959).

“The poster format is a unique form of biography,” says Bassoff, a memorabilia collector whose two decades of searching have yielded some 3,200 pieces. “It’s an inadvertent biography in the sense that you watch Flynn basically deteriorate in the artwork.

“A lot of collectors only seek the classic films. They disdain the later ones. But one picture from ‘The Big Boodle’ [a 1957 film noir] says a thousand words about Flynn.”

The book also provides a fascinating glimpse into the largely lost art of illustrated movie posters.

“Today’s posters--not to denigrate them--are video box covers. Theaters don’t display much anymore; the image is used in the ad campaign in the paper, then it goes on the video box.

“Old movie posters look much more exotic and artistic. They make you want to see the movie right now. No matter how old they are, they’re very undiminished in their capacity to incite your imagination.”

Bassoff, 42, first fell under the spell of Flynn as a child in New Jersey, watching 1950s TV airings of “The Sea Hawk” and “Captain Blood.”

“Flynn gave voice to the swashbuckler,” he says. “That’s why as a boy I liked him. Errol Flynn looked like he was inhabiting history and having a great time doing it.”

It was a movie career made seemingly by chance, after Flynn bounced through a string of failures and embarrassments in his native Australia--including school expulsions, job firings and, according to the actor, being tried for murder in a jungle shootout.

A fluke meeting led to Flynn’s being cast in 1932 as mutineer Fletcher Christian in the low-budget Australian film “In the Wake of the Bounty.”

“It whetted his appetite for acting,” Bassoff says. “To him, it was easy money.”

Even greater success came when Flynn began his string of Warner Bros. blockbusters in 1935, a career step vividly captured in Warner star-building posters and lobby displays.

But according to the author, Flynn’s effortlessness in front of the camera proved a source of ongoing frustration.

“People didn’t take him seriously. They said, ‘He can play Robin Hood--that’s not acting.’ Of course, we know that’s incredible acting.

“Watch ‘Robin Hood’--he’s bigger than the movie. It’s a huge movie--Technicolor, cast of thousands, actors stealing scenes from each other like barking dogs. But every time Flynn opens his mouth, the movie stops, and everybody sits there and listens to every word.”

Despite Flynn’s enduring image, Bassoff found himself fighting off critics of his own when trying to find a publisher for the book, which he describes as the first poster-art volume devoted to a single actor.

“People would say, ‘Why Errol Flynn?’ which flabbergasted me,” he recalls. “Don’t people have a hero?”

As a result, Bassoff drew on past career experience in marketing and advertising, and published the book himself, retaining complete control. (His timing proved fortuitous: 1995 marks the 60th anniversary of “Captain Blood,” Flynn’s breakthrough film.)

Bassoff has also kept an eye on the skyrocketing amounts being paid for classic movie posters; the current record-holder is a “Frankenstein” one-sheet, sold in 1993 for $198,000.

“Science fiction and horror are the big-ticket items. It’s hard for beginners to get into collecting at the poster level now, but there are still bargains around.

“I think the rule of thumb for anyone is: Collect what you like. That’s what I started doing. I was staked to a grubstake by fate.”

Recently, Hollywood has revisited Flynn’s arena of historical adventure, with films such as “Braveheart,” “Rob Roy” and “First Knight” (which ranged from break-even to bust at the box office).

But what the industry now lacks, according to Bassoon, is an action star of Flynn’s enduring magnitude.

“I think whatever he was, what lives in those movies is an incredible screen hero who lived in a time in Hollywood that people would sell their right arm to have been in.

“One can only imagine being someone to whom everyone is offered. It’s a fantasy . . . but is it really great? Look at how Errol Flynn ended up.”*