When OK Computer was released in the spring of 1997, it was instantly greeted with ravenous acclaim. According to the music press, Radiohead’s third album was pushing the boundaries of rock, it was about modern life; it was Important. And so, the band’s fans poured over every lyric and every detail in the CD artwork in an effort to divine what sort of serious concept album this was, misunderstanding that sometimes Radiohead was just goofing around.

For example, “Paranoid Android” – considered by many to be the album’s centerpiece with its multiple parts presenting Radiohead as both visceral and tender – wasn’t constructed to be a ponderous, prog-rock epic. Rather, the album’s second track began as three separate pieces written by three different members of the band. In an alcohol-fueled session, the boys mashed together the different segments, inspired what the Beatles did on Side Two of Abbey Road and resembling John Lennon’s constantly shifting “Happiness is a Warm Gun.” There were other musical inspirations, too.

“Well, when we wrote it, one of the references was [Queen's] ‘Bohemian Rhapsody.’ But the other was the Pixies,” guitarist Ed O’Brien admitted to Melody Maker in 1997. After release, “Paranoid Android” was even called “the ‘Bohemian Rhapsody’ of the ’90s – a description guitarist Jonny Greenwood shrugged off. “It’s not actually complex enough to be ‘Bohemian Rhapsody,” he said. “There’s only really two different bits there. Plus it’s way too tense.”

Tense? Sure. But “Paranoid Android” actually has four parts – the prickly, acoustic beginning; the raging, squealing guitar freakout; the softly moaning “rain down” part and a violent reprise of the second section as the coda. Still, Greenwood’s point about simplicity is a good one. The song stays in 4/4 time throughout (with the exception of a bit of 7/8 as the narrator is about to become unglued) and doesn’t attempt the pretensions or grandeur of ’70s rock epics. After all, as Thom Yorke sings on the song, “Ambition makes you look pretty ugly.”

Yorke claims he wrote the words to the separate movements in different headspaces. Some of the lines were inspired by an incident in a Los Angeles bar when he was next to a group of coked-up friends. When one of the women had a drink spilled on her, she went ballistic and turned into an angry figure that the singer found “inhuman.”

“There was a look in this woman’s eyes that I’d never seen before anywhere,” Yorke told Q. “Couldn’t sleep that night because of it.”

Watch Radiohead's 'Paranoid Android' Video

But instead of simply excoriating the woman (although he did direct the line “kicking squealing Gucci little piggy” at her), he took a widescreen view of this slice of humanity. As a narrator on the song, Yorke displayed impotent rage, distanced bemusement and outright sarcasm (“God loves his children, yeah”). For the title, he picked “Paranoid Android” – not only as a comedic reference to Marvin the Paranoid Android in Douglas Adams’ The Hitchhiker’s Guide to the Galaxy, but as a play on his own ponderous public persona.

The title “was chosen as a joke,” he told Jam!. “It was like, ‘Oh, I’m so depressed.’ And I just thought, that’s great. That’s how people would like me to be.”

When Radiohead road-tested some of the OK Computer material during a 1996 opening slot for Alanis Morissette, the band’s humor pervaded performances of the early version of “Paranoid Android.” It became a send-up of prog-rock, with Yorke facetiously introducing the song as a Pink Floyd cover and the running time sometimes pushed past 14 minutes by a long Jonny Greenwood organ solo.

Watch Radiohead Perform "Paranoid Android"

“When we started playing it live, it was completely hilarious,” O’Brien recalled. “There was a rave down section and a Hammond organ outro, and we’d be pissing ourselves while we played. We’d bring out the glockenspiel and it would be really, really funny.”

When Radiohead returned to the studio, they edited down the expansive version to a tidier six-and-a-half minutes for OK Computer. It took the band the better part of a year to re-learn how to play “Paranoid Android” in its shorter incarnation for the tour.

Not only was it Radiohead’s most epic composition to date, positioned prominently on the album as its second song, the band decided to make “Paranoid Android” the lead single off OK Computer. Making this expansive effort the first impression of the new disc was a bold move and probably not one the band’s record label, EMI, would have made on its own. But the single, released on May 26, made a clear statement about what listeners might expect from Radiohead in 1997 – and it wasn’t The Bends, Part II.

“‘Paranoid Android’ is the song we play to people when they want to know what the album’s like,” O’Brien told Melody Maker, “’cos it should make them think, ‘What the f--- is going to happen on the rest of the album?’”

Radiohead continued its joke about prog/Pink Floyd on the artwork for the CD single, which featured the image of a pig (possibly a reference to the “Pigs on the Wing” on Animals, although it could also be a nod to the “piggy” in the lyrics) as well as two stick figures shaking hands (with a profile that seems to mimic the cover of Wish You Were Here). They also sought to deploy humor in another visual element for its video.

“When it came time to make the video for that song, we had lots of people saying, ‘Yeah, great, we can have another video like ‘Street Spirit,’ all moody and black and dark,” Yorke said. “Well, no. We had really good fun doing this song, so the video should make you laugh. I mean, it should be sick, too.”

"Sick and funny" is a solid, concise description of the simple-yet-grotesque cartoon directed by Swedish animator Magnus Carlsson, who brought together images of helicopter angels, tree-bound flashers, EU statesmen and mermaids with Radiohead’s dramatic song. The video became a favorite on both sides of the Atlantic, with American MTV putting an edited version (which blurred the mermaids’ cartoon breasts) on heavy rotation.

Although the clip exposed a lot of Americans to the song, it didn’t make the single a chart success, possibly because fans were still expecting another "Creep." But in the U.K., the tune became the band’s biggest hit to date. “Paranoid Android” hit No. 3 on the British charts, with Radio 1 eventually playing the six-and-half-minute tune up to a dozen times every day. Yorke and the band would revel in this circumstance. Being able to make a hit single out of such a strange song became one of the defining successes of OK Computer.

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