Michael Jackson is 19 or 20, and he is wearing an electric purple suit, and his Afro adds at least a foot to his height.

Jackson enters the cramped office of Studio 54 nightclub impresario Steve Rubell as a television journalist is interviewing Rubell.

“Hi Michael, come on in,” says Rubell. “This is Jane Pauley.”

Pauley says, “When you hear the name ‘Studio 54,’ does your pulse quicken, do your feet start moving?”

“I’m ready to have a good time,” says Jackson. “It’s where you come when you want to escape. It’s escapism.”

Escapism — and debauchery and spectacle and intense stimulant-fueled partying — to rival anything we’d ever seen in the 20th century.

Some four decades after the New York club blazed like a comet across the nightlife landscape, director Matt Tyrnauer’s “Studio 54” is an energetic, colorful, warts-and-all reminder this was arguably the most famous (and infamous) American establishment of its kind. (If not Studio 54, what’s your nominee?)

It’s gossipy, but well-researched. It’s fun and campy, but sometimes sobering and occasionally melancholy.

The doc provides a brief but thorough prologue explaining how the dynamic duo of Ian Schrager and Steve Rubell (both natives of Brooklyn) met at Syracuse University and teamed up for a couple of middling ventures before going big and bold with the 1977 launch of Studio 54 at 54th Street and Eighth Avenue in a cavernous space that was once home to the CBS studios for game shows such as “What’s My Line?” and “The $64,000 Question.”

As journalist Bob Colacello explains: “Gay clubs were some of the first to have disco music, but disco was black music and it came out of black clubs. The beautiful models would go to the gay clubs with the designers and hairdressers and makeup artists, and then the straight guys would want to meet the models so they would go to those clubs, and it all started blending [at Studio 54].”

Pioneering disco/funk/dance music legend Nile Rodgers notes, “This was revolutionary. It was the first time people were non-judgmental, [where] everyone was welcome.”

MORE FROM RICHARD ROEPER

‘The Oath’: Politics divides Thanksgiving table in an edgy social satire
New ‘Halloween’ stays true to splatter movie traditions

Director Tyrnauer liberally sprinkles in a dizzying array of black-and-white stills and color film footage, giving us a front-row seat to the madness, from the throngs of hopefuls who lined up every night, hoping to get past the velvet rope; to the seemingly endless parade of celebs, from Bianca Jagger to Liza Minelli to Cher to Truman Capote to Farrah Fawcett to Warren Beatty to Andy Warhol to Diana Ross; to half-naked waiters serving the half-naked clientele; to the lavish production numbers that looked like something out of a Hollywood studio musical.

There were mattresses in the basement. Actual mattresses in the basement. And not for taking naps.

Rubell was a publicity-seeking heat missile and party animal who strolled the club in a giant puffy winter coat stuffed with drugs and cash and courted favor with celebrities and the media, while Schrager was the behind-the-scenes operator trying to keep it all together.

In a New York Magazine profile, Rubell said of the club’s profits, “Only the Mafia does better, but don’t tell anybody.”

Steve Rubell (left) and Ian Schrager stand outside Studio 54 in 1978. | Photofest

Cut to Dec. 14, 1978, when the IRS raided the club and found drugs on the premises. Despite the efforts of some 37 attorneys — including the notorious Roy Cohn — Schrager and Rubell eventually wound up serving 20 months apiece.

It helps greatly that Schrager (who later turned to running a string of high-end hotels and is now 72) sat down for extensive interviews with the filmmakers and is honest and straightforward as he looks back at the highs (in more ways than one) and the lows.

Rubell died at 45 from AIDS-related complications — but he’s a dominant presence in the film, through archival footage and audio snippets of long-ago interviews.

The original Studio 54 lasted for only 33 months. In 98 minutes, “Studio 54” captures the club on its best nights and on its worst mornings.

‘Studio 54’

Zeitgeist Films presents a documentary directed by Matt Tyrnauer. No MPAA rating. Running time: 90 minutes. Opens Friday at the Music Box Theatre.