“If you wrote some of this stuff and put it in a novel, no one would believe it; but when you write the facts, you can indulge in the most outrageous irony because it happened to be the truth!”

Author Robert Hofler is referring to incidents recounted in his new book, Party Animals, which tells the story of flamboyant producer Allan Carr. One of the few out, open and proudly gay personalities in Hollywood, Carr never lied about his sexual orientation, and this was in a town which, the writer notes, “has always been among the most homophobic in the United States.”

“Even though he hung out with a lot of women, it was always ‘I’m out with my friend,’ ” he says. “It was never, ‘This is my date or my fiancé.’ He wasn’t very political, but he was the first one who was really kind of out there.”

Anyone who knows even the slightest bit about show biz in the 1970s is likely to be familiar with this prime mover’s work, if not the man himself. He had his share of successes — most notable was the film version of Grease (which remains the highest-grossing movie musical ever in America).

On stage, he broke new ground with the Tony Award-winning La Cage Aux Folles, which was the first Broadway hit to depict an openly gay couple in a loving, long-term relationship (not to mention a full chorus of drag queens!).

Nonetheless, what makes his story truly riveting was how, right along with these soaring triumphs, he was likewise responsible for some of the most monumental bombs in cinematic history. Among them were Grease 2, Where the Boys Are ’84, and the so-bad-it’s-nearly-good Can’t Stop the Music. In fact, recounting the making of these projects is what makes Party Animals one genuinely sizzling read.

Hofler, who is a senior editor at Variety, also wrote The Man Who Invented Rock Hudson, which chronicles the life of Henry Wilson, another behind-the-scenes figure in gay Hollywood’s past. He was the agent responsible for discovering such ’50s-era idols as Rock Hudson, Tab Hunter and Troy Donahue.

In that book, as he does in Party Animals, Hofler paints a vivid picture of a larger-than-life legend who had a great fall.

“While I was working on ‘The Man Who Invented Rock Hudson,’ I didn’t really find very much to read about Henry Wilson. So that whole story of this gay agent who developed and nurtured these illustrious names is one of the great Hollywood stories of a great, gay life, and that’s also the way I feel about Allan Carr. His is a real roller-coaster ride — a very dramatic, theatrical existence, and now it won’t be lost.”

Despite a somewhat lethargic prologue, Hofler creates an engrossing, fast-paced narrative. Included along the way are plenty of interesting bits of trivia such as how Henry Winkler and Marie Osmond were originally considered for the leads in Grease, while the role of Rizzo had initially been promised to Lucie Arnaz. Later, he reveals how Lorna Luft wisely declined when the producer approached her to play Snow White in the now infamous opening number of the disastrous 1989 Oscar telecast that many credit with bringing his career to an end.

Many more stories, ranging from mild to wild, are skillfully interwoven throughout. (The chapters dedicated to “Can’t Stop the Music” — Allan’s no-holds-barred salute to disco, starring The Village People — could by themselves turn this book into an instant “peek behind the celebrity curtain” classic!)

“Back in the Sixties, we used to have these things called ‘happenings’ in interesting venues, and Allan Carr took that concept and ran with it,” the entertainment journalist says.

Two of the most notable events profiled in the book involve Carr’s opening-night gala for the movie Tommy in 1975, which he threw in (of all places) the New York subway!

Another time, “He threw a big party for Truman Capote in a jail-house in downtown L.A.” the biographer explains, an homage to In Cold Blood, Capote’s book about the murder of a family in Holcomb, Kan.

Subtitled A Hollywood Tale of Sex, Drugs, and Rock ’n’ Roll Starring the Fabulous Allan Carr, the book opens with Carr’s 1973 purchase of a house on Benedict Canyon Drive that had belonged at various times to Ingrid Bergman, Kim Novak and James Caan. Dubbed Hill Haven Lodge, this was quickly to become the site of parties that brought Hollywood hedonism to new heights throughout the 1970s.

“He not only had the prime A-list movie and TV stars at his parties, but he also brought in rock stars like Rod Stewart, Ringo Starr, Elton John and Mick Jagger — this mixing movies and rock-and-roll was completely new to Hollywood.”

Hofler emphasizes that the colorful caftan-wearing character also had great respect for members from Hollywood’s Golden Age, and often the guest list would include the likes of Mae West or Rita Hayworth. Yet the chief attraction of these star-studded soirees was all those young, beautiful -- and sexually available -- boys and girls.

“Throughout the book, people talked about how there would be some big movie star chatting up the pool boy from next door,” Hofler says.

However, when it came to Allan’s own sexual exploits, he frequently used the direct approach by pointedly asking: “cash or career?”

Hofler stresses, though, that despite numerous overindulgences, perhaps Carr’s greatest strength was that he was the consummate showman.

“He created publicity by giving outrageous parties and saying outrageous things. In short, here was the last real master of the publicity stunt.”

On the other hand, Hofler wistfully concedes that it was exactly this sense of excess that ultimately cut Carr’s time in the spotlight devastatingly short. “His crushing flaw was that he simply didn’t know when too much was enough. I think he was really a tragic hero.”

Carr died of liver cancer in 1999 at age 62.

A must-read for show queens, movie buffs, or anyone who experienced those free-wheeling post-Stonewall, pre-AIDS times (not to mention those who wish they had), Party Animals is now available from Da Capo Press at bookstores everywhere.