The fever hit hard. Toward the end of 1977 and through the following year, a single album inspired millions of listeners to put on formfitting polyester and hustle their way to the nearest dance floor. This of course was the soundtrack to Saturday Night Fever — a box-office smash that made John Travolta a movie star and effectively mainstreamed the sounds of disco. The film was a hit, but the soundtrack became a true pop culture phenomenon, dominating the Billboard 200 for 24 weeks, spawning four No. 1 singles and five GRAMMYs, including Album Of The Year for 1978.

The album's fever-inducing funkiness was largely the work of 2015 Recording Academy Lifetime Achievement Award recipients the Bee Gees (brothers Barry, Robin and Maurice Gibb), who performed six of the soundtrack's tunes and wrote seven, including "If I Can't Have You" for singer Yvonne Elliman. They would take home Producer Of The Year (with Albhy Galuten and Karl Richardson) for their work on the project.

The disco era is long gone, and the polyester's been consigned to the closet (or the recycling bin), but this album remains a powerful collection. Following are 10 lesser-known facts about the soundtrack that produced the heat behind Saturday Night Fever.

1. The Bee Gees did not become involved with the film until post-production.

Robert Stigwood, film producer and head of the Bee Gees' label RSO Records, commissioned the group to write five songs, including "Stayin' Alive," "If I Can't Have You" and "How Deep Is Your Love." Before the brothers signed on, Travolta boogied on set to songs by artists such as Stevie Wonder and Boz Scaggs. 

2. The Bee Gees didn't start out as disco kings.

In the '60s and early '70s the trio had a string of Beatlesque pop hits such as "Holiday," "I Started A Joke" and "Lonely Days." The Saturday Night Fever soundtrack is often credited with reviving their career, but their falsetto-driven disco sound was first showcased two years before the film was released on the 1975 chart-topper "Jive Talkin'," which was used in one of the film's deleted scenes, but ultimately remained on the soundtrack album. Their 1976 No. 1 hit "You Should Be Dancing" is also on the album.

3. Saturday Night Fever was based on a 1976 New York magazine article.

"Tribal Rites Of The New Saturday Night" examined the real-life disco subculture in Brooklyn, N.Y., and was the original working title of the film. When it was shortened to "Saturday Night," the Bee Gees suggested it would be catchier if it was extended by one word to include the title of their new song "Night Fever," which appears in the film during a well-choreographed line dance performed by Tony Manero (Travolta), and others. 

4. "More Than A Woman" appears twice in the film and on the soundtrack, performed by groups of brothers.

In addition to the Bee Gees' version (written by the trio), a cover by R&B group Tavares is featured. Brothers Ralph, Pooch, Chubby, Butch, and Tiny Tavares' version cracked the Top 40 on the Billboard Hot 100.

5. "A Fifth Of Beethoven" ushered in the odd, short-lived trend of setting symphonic works to disco beats.

The No. 1 song was credited to Walter Murphy & The Big Apple Band, though Murphy himself was "the band" for all intents and purposes, playing almost every note of the recording. His label tacked on "& The Big Apple Band," believing the song would be better received if credited to a group. 

6. Non-Bee Gee brother Andy Gibb pushed "Stayin' Alive" from No. 1 with "(Love Is) Thicker Than Water."

"Stayin' Alive" held the top spot on the Billboard Hot 100 throughout February 1978 until it was nudged by none other than Andy Gibb's mid-tempo hit. Andy's older brothers weren't out of the top spot for long. Two weeks later, the Bee Gees bumped him from No. 1 with "Night Fever."

7. The Trammps' "Disco Inferno" was inspired by another film, The Towering Inferno.  

First released in 1976, songwriters Ron Kersey and Leroy Green said the lyrics for "Disco Inferno" were inspired by the classic 1974 disaster flick, which included scenes of a high-rise disco literally burning down. Philadelphia band the Trammps scored their biggest hit with the song, which is one of the more energetic on the soundtrack, and backs some of the hottest dancing in the film.

8. The soundtrack features Walter Murphy and Yvonne Elliman's only No. 1 hits.

Murphy scored with "A Fifth Of Beethoven" and survived the disco years to become an esteemed film and television composer whose credits include "Family Guy" and Ted. Elliman, who delivered "If I Can't Have You," took a hiatus from releasing music after 1979's Yvonne, but resurfaced in 2004 with a five-track EP, Simple Needs.

9. "Disco Duck" didn't make the album cut.

A scene in the film shows a dance instructor teaching a class of senior citizens how to get their disco groove on. The song they awkwardly hustle to is the 1976 Rick Dees' novelty "Disco Duck." According to Dees, his agent at the time refused to license the song for the soundtrack, which went on to become the second biggest-selling soundtrack album of all time. "He told them it would compete with sales of my own album," Dees regretfully told the Los Angeles Times.

10. Saturday Night Fever is the only disco album to win a GRAMMY for Album Of The Year.

The album is also one of three film soundtracks to win the prestigious honor, preceding Whitney Houston's The Bodyguard — Original Soundtrack Album (1993) and O Brother, Where Art Thou? — Soundtrack (2001).

(Chuck Crisafulli is an L.A.-based journalist and author whose most recent works include Go To Hell: A Heated History Of The Underworld, Me And A Guy Named Elvis, Elvis: My Best Man, and Running With The Champ: My Forty-Year Friendship With Muhammad Ali.)