One of the most chaotic and notorious musical performances in Saturday Night Live history took place on Halloween 1981.

Fear, a Southern California punk rock band, were the night’s guests. The group was far from a household name, having mainly cut its teeth in the underground scene. Punk documentary The Decline of Western Civilization - filmed in 1979 and 1980 before being released in July 1981 - had given Fear their biggest spotlight so far.

But the band had one major thing working in their favor, a die-hard fan by the name of John Belushi.

The comedian had become enamored with Fear after catching their performance on a local Los Angeles-based music TV show. He sought out the group, befriended the members and initially tried to get them involved in his latest project, a film called Neighbors. Belushi convinced the band to record a song that could be used over the comedy’s end credits.

“I wasn’t looking forward to singing lyrics that I had written for someone else to sing that were based on a movie that didn’t touch my life,” Fear front man Lee Ving recalled decades later to Rolling Stone. Instead he tried to get Belushi to handle the vocals himself. Eventually, both men sang on the track, which was appropriately titled “Neighbors.” But while Belushi loved the collaboration, studio executives felt differently and outright rejected it.

Listen to 'Neighbors' by Fear (feat. John Belushi)

Feeling as though he’d let Fear down, Belushi promised to get the band a performance on Saturday Night Live. As one of the show’s most successful and beloved alumni, the comedian knew he’d be able to pull some strings. Also working in his favor: the program’s sagging ratings.

First, Belushi got SNL head writer Michael O’Donoghue on his side. Then to seal the deal the Animal House star agreed to make a guest appearance in the Oct. 31, 1981, episode if Fear could be the night’s musical guest. The deal was made, but Belushi wasn’t done working.

Determined to make the performance as authentically punk as possible, Belushi reached out to associates in the D.C. area and had them bus up for the taping.

“He wanted 15 to 20 people,” Ving explained, “but they stopped in Baltimore and Philly before they got to New York and arrived with 35, 40 people.”

That evening’s Saturday Night Live was hosted by Halloween star Donald Pleasence, but it was Fear who stole the show. The band rocked through songs "Beef Bologna" and "New York's Alright if You Like Saxophones" while their loyal fans went nuts on the studio’s floor. Suddenly, frenzied mosh pits were taken out of the dark, sweaty clubs and shoved directly onto TV screens across America.

“The real audience at Saturday Night Live was scared to death,” Ving admitted, noting that his band’s fans took over. “They didn’t know what was happening with all the mayhem.”

Watch Part of Fear's 'Saturday Night Live' Performance

The punk fans became unhinged, breaking production equipment, throwing a pumpkin into the chest of SNL producer Dick Ebersol and, in one particularly chaotic moment, grabbing a microphone and screaming expletives on live television. The latter offense was the final straw, as the network cut away to a prerecorded Eddie Murphy sketch.

“The main NBC guy was at home watching with his wife and freaked out, calling the station saying, ‘Go to stock footage. Cut, cut, cut!” Ving recalled.

Headlines afterward would describe the scene as a riot, with the New York Post claiming the show’s staff was “glad to be alive” following the event. "I've been in the business for years, and I've never seen anything like this," one unnamed NBC technician told the Post. "This was a life-threatening situation. It's amazing no one was killed."

A Saturday Night Live spokesperson disputed such reports, claiming the severity of the damage - which some estimated to be $200,000 - was much less. “Nobody was hurt, and nothing was smashed,” the rep explained to Billboard. “There was no smoking ruin.”

Still, Fear’s antics earned them a lifetime ban from SNL, something Ving admitted he took pride in. “They swore that night they’d never rebroadcast our footage,” the singer  revealed. “As a result, I have become one of the esteemed members of the permanently banned.”

15 Guests Who Were Banned From 'Saturday Night Live'