Here's a clip in case you've forgotten:
The iconic film, released in 1977, helped define a generation and earned John Travolta his first Academy Award nomination at age 24.
To celebrate the anniversary, Paramount is releasing a new director's cut of Saturday Night Fever on Blu-ray and DVD on May 2.
Director, John Badham added scenes to the R-rated original which enrich the plot and fill out Travolta's character.
Badham knew when he first read the script, the movie was special. As he tells it, the script arrived when he was ill -- a fever of 101 degrees, no less -- with strict instructions not to read it as his agent was trying to make a deal for Badham to direct.
Of course, Badham read it anyway.
"An hour later or whenever I finished, I was cured. I so fell in love with this character Tony Manero," said Badham by phone. "The world felt so real. It was a tough world to live in. There was a lot of humor to it and the way people related to one another. There was a boisterousness to it that I found terrifically fun."
The film was based on a 1976 New York Magazine article about a Brooklynite named Vincent who writer Nik Cohn later said was a fabrication. For the movie, they renamed the lead character after the very real Tony Manero, a fixture at Brooklyn night clubs who was a decent dancer but mostly kept to himself and was nothing like the character Travolta would bring to life on-screen.
Badham who grew up in Birmingham, Ala., had never been to Brooklyn, but he felt he understood the characters and he was enthusiastic about their lives. During filming, he pretended he was a documentary filmmaker. He would go up to extras on set and ask them how they would react, for example, to a Puerto Rican or black couple dancing at the club. The answers he got sometimes shocked him.
"Though I had grown up in the racist, segregated South, it wasn't much different in the Northeast. People were just as overt about it," he said.
Viewers see that dynamic played out on-screen during a major turning point for Travolta's character. Tony Manero decides to hand his award over to the Latino couple that had been shut out. At that moment, viewers know Manero sees his world for what it is and that he has decided to go a different way.
While most everyone remembers Travolta dancing to the hit soundtrack by the BeeGees, Badham notes that when people see the film now, they are often reminded of what a dark movie it is. Travolta's character in particular is mean to his parents and has bad relationships with people, Badham said.
In this director's cut, he takes the opportunity to restore a few character scenes that were trimmed at the last minute and show the softer side of Tony Manero's personality.
In one such scene, after Manero has an argument with his friends and jumps out of the car, he catches sight of his beloved Verrazano Bridge, and without saying a word lifts his finger to the sky and traces it with his finger.
One scene that was cut and remains in the vaults (they are unable to get the proper rights) shows Travolta dancing to "Disco Duck" by Rick Dees.
"We cut it out of the movie and never put it back in," Badham said. "It is funny and he does it as a robotic dance."
Badham has many memories about the film, but mostly, he said, it was just a movie that came together in the way that actors and directors hope any project would.
"It certainly worked and I think everybody that acts or directs or does anything they care passionately about tries to make everything work. Somethings just gel better than others," he said.
The celebration of the 40th anniversary of the film began earlier this year. Travolta reunited with Barry Gibb for 'Stayin' Alive: A GRAMMY Salute to the Music of the Bee Gees' featuring popular artists such as Celine Dion, John Legend, Andra Day and more paying tribute to the music of the BeeGees.