Demos are a great way for listeners to peer into the creative process of their favorite musicians. As an artist’s vision comes to fruition, demos serve as the solidified rough draft of a song. They can show us the painstaking mental labor that comes with writing new music. They also portray the auditory and lyrical evolution of a track. While most demos never see the light of day, others are usually unveiled long after the mastered track drops. Mastered tracks can be engineered and produced to cater to an audience. Meanwhile, demos offer the organic, initial elements of a song. Here are 15 songs that took on completely new identities from their original demo.

“REALiTi” – Grimes

Grimes’ demo for “REALiTi” offers a bare, mesmeric sound compared to the finalized version from her 2015 album, Art Angels. Whereas the album version fits seamlessly with the indie-pop sound of Art Angels, the demo resides closer to something off Grimes’ 2012 album Visions, with its delicate vocals and synth-wave sound. In the description of the music video on YouTube, Grimes explains the demo is from “the lost album” from early 2013 and wasn’t mixed, mastered or even meant to see the light of day. However, we’re thankful it did.

“Manic Monday” – Prince

Prince wasn’t just releasing the most transformative songs of the 1980s — he was penning them for other artists as well. While “Manic Monday” was performed and released by ‘80s pop-rock girl group the Bangles in 1986, the demo was originally written and recorded by Prince in 1984. Prince’s demo stays true to the lyrical style that we see in the mastered version. Despite knowing this track as a hit from the Bangles, Prince could have easily released a mastered version of this demo on his 1986 album Parade, and we’d be none the wiser.

“Psycho Killer” – Talking Heads

Talking Heads1975 demo of “Psycho Killer” is remarkable for many reasons — mainly because it's one of the earliest recordings of post-punk. Compared to the mastered version on Talking Heads’ debut 1977 album, 77, the demo is much quicker in tempo and contains a softer, more fluid lyrical style. Lead singer David Byrne delivers the lyrics in a more muted manner, giving the song a lighter tone and all-around experimental sound compared to the album version.

“Queen Bitch” – The Notorious B.I.G.

Like Prince, the musical genius of the Notorious B.I.G. can be seen in the songs he wrote for other artists. His impeccable flow is shown in this demo for “Queen Bitch,” a song eventually released by Lil’ Kim on her 1996 album Hard Core. The demo and finalized versions aren’t too different other than a slight adjustment to the piano sample. However, this rare demo gives us a peek into the brilliance of Biggie, as well as his lyrical ingenuity.

“I’ll Try Anything Once” – The Strokes

“I’ll Try Anything Once” went through major transformations before it eventually became the song the Strokes fans know as You Only Live Once.” The demo’s overall tone is completely different, with a somber lyrical style that sounds more like an alt-rock lullaby than the opening track off their 2006 album, First Impressions of Earth. While the melody remains the same, the demo’s lyrics are more intimate and specific about romantic complications.

“Disenchanted” – My Chemical Romance

The finalized version of “Disenchanted” by My Chemical Romance is a seamless fit for their 2006 album, The Black Parade. However, the raw sound of the demo gives the phrase “emo anthem” a whole new meaning. With a tad more rasp and angst in his voice, Gerard Way’s vocals create a more intimate and angsty tone for “Disenchanted.”

“Once I Had Love/The Disco Song” – Blondie

Heart of Glass” is one of Blondies most recognizable hits, with its disco-infused beat and Debbie Harry’s rich vocals. Before the song became a new-wave chart-topper, however, its demo was strikingly slower and more laid back. Despite its unique difference in musical composition, the core sound and vision for the track are evident in the demo. 

“Dreams” – Fleetwood Mac

This stripped-down demo of the generation-spanning hit “Dreams” by Fleetwood Mac was made to be listened to by candlelight. Backed by just guitar, Stevie Nicks’ hypnotizing voice amplifies the mystical tone present in the finalized version. The bare elements of this demo give listening to this song a new freshness compared to the mastered version. It’s less mixed, allowing for a more intimate and transcendent listening experience.

“Love Is A Losing Game” – Amy Winehouse

Amy Winehouse serenades the heartbroken in “Love Is A Losing Game.” While both versions are somewhat similar to each other, Winehouse’s voice is unpolished yet more intimate and emotional in the demo. With just a guitar featured alongside her vocals, this demo allows a more intimate and personal touch to come through.

“Miss World” – Hole

The demo for “Miss World” is a raw cut of the lead single from Hole’s 1994 album, Live Through This. With the chorus devoid of lyrics, lighter guitar throughout the verses and softer vocals illuminate themes of self-image and substance misuse. Courtney Love’s vocal style is more raw and unpolished as well. It perfectly corresponds to the narrator’s struggle between outer beauty and mental anguish. By toning down the overamplified grunge sounds, this demo lets Love’s vocals shine and the emotional pain of the track seep through.

“Bullet With Butterfly Wings” – The Smashing Pumpkins

This acoustic demo offers a subdued take to the Smashing Pumpkins1995 hit “Bullet With Butterfly Wings.” The demo doesn’t possess the heavy crescendos and Billy Corgan belting the chorus, but that doesn’t keep this version being any inferior. Corgan’s delicate vocals — almost a whisper at the beginning — highlight the pains of the band’s success. After hearing the album version, this demo traces the track back to its bare structure and vocals.

“10:15 Saturday Night” – The Cure

The mastered version of “10:15 Saturday Night” features the post-punk sound of the Cure’s debut album, Three Imaginary Boys. The song is derived from lead singer Robert Smith spending a Saturday night in a morose, lonely state. The demo, however, amplifies Smith’s state and holds drawn-out anguish brought in by the synths in the outro. 

“Black Hole Sun” – Soundgarden

In what would become Soundgarden’s most popular song, “Black Hole Sun” embodies a surreal, dystopian dreamscape. The mastered version went on to become a grunge anthem of the 1990s. The demo, on the other hand, is rooted in psychedelic influences. Multiple guitars bleed over each other in the verses, while Chris Cornell’s vocals echo off one another. It’s a slightly slower yet clearer alternative to the popular track. Minus all the heavy, grunge-y guitars.

“I’m With You” – Avril Lavigne

As a pioneering figure of the early 2000s pop-punk scene, Avril Lavigne proved her versatility with her alt-rock ballad “I’m With You.” The demo showcases Lavigne’s vocals without the overproduction of the song’s sound. The background orchestra is more apparent in the demo, too. It adds to the overall ballad sound of “I’m With You” and highlights the isolation and loneliness in the lyrics. 

“Sappy” – Nirvana

This slower demo of Nirvana's 1993 song “Sappy” is derived from a home recording of lead singer Kurt Cobain dating back to the 1980s. Cobain’s lowered voice and monotone vocals create the lamentful tone. Meanwhile, the melody and guitar add a repetitive, yet hypnotizing, element.