Twenty-five years ago, Madonna changed. Sure, Madonna was always changing, but with the release of Erotica on Oct. 20, 1992, she fully shed her ebullient '80s pop skin, donned a leather cat mask, and kicked open a rusty back alley door that previous chart-toppers only dared to scratch at.

You didn't need to pick up a copy of her celebrity nude-filled coffee table book, Sex, to realize it. You didn't even need to see Madonna Veronica Louise Ciccone, whip in hand, mugging for the camera in the video for the title track. All you needed to do was press play on the album and let the impossibly thick, libidinous bass line of "Erotica" start vibrating throughout your body. Forty seconds in, the sampled horns of Kool & the Gang's "Jungle Boogie" flare up, but instead of sounding reassuring and familiar, they seem disembodied and eerie. Then, Madonna's latest alter ego addresses you, low and firm: "My name is Dita / I'll be your mistress tonight."

If her earlier work was an invitation to celebrate sexuality without shame, Erotica was a challenge from Dita Parlo – Madonna's unashamed, unflinching dominatrix persona – to witness and perhaps even indulge in society's sexual taboos. Madonna may have addressed the male gaze before, but on Erotica, she wasn't just staring back – she was making the world her sub.

Erotica occupies a watershed place in the pop pantheon, setting the blueprint for singers to get raw while eschewing exploitation for decades to come. For its 25th anniversary, Billboard spoke to the players involved in Madonna's most creatively daring release. Here's what producer-writer Andre Betts, backup singer Donna De Lory, producer-writer Shep Pettibone, co-writer Tony Shimkin and Living Colour bassist Doug Wimbish recall of the writing and recording of Erotica, the insane release party for the LP and book, and the collective societal pearl-clutching that followed.

The seeds of Erotica trace back to 1990's The Immaculate Collection, which included two new songs: "Rescue Me" from Shep Pettibone and his assistant Tony Shimkin, and "Justify My Love" from Andre Betts and Lenny Kravitz. The gospel-house of the former hit No. 9 on the Billboard Hot 100, while the hip-hop-inflected latter – which scandalized the world with its leather-clad, ambisexual music video -- reached No. 1. For Erotica, Madonna reteamed with Pettibone and Shimkin for 10 tracks, and Betts for four.

Tony Shimkin: After doing The Immaculate Collection and "Rescue Me," she let us know she was working on a new album and wanted us to be involved in the writing. Seeing I was a musician and writer and Shep [Pettibone] was more of a DJ and remixer, we collaborated on the writing of the tracks for the Erotica album. We went up to meet with her in Chicago, post-"Vogue," when she was filming A League of Their Own. So we met with her and started to get to work on some music, and sent it to her as we were working our way through it. She would come into New York and have a book full of lyrics and melody ideas and we started working together in Shep's home studio. I believe the first time she was in New York for an extended period, we were working on "Deeper and Deeper" and "Erotica" and "Bye Bye Baby." She's very driven. There's was never a period of feeling it out -- it was diving in headfirst.

Doug Wimbish: I remember Madonna when she used to go to the Roxy before she got really put on. I'd see her at the Roxy when Afrika Bambaataa was down there or [Grandmaster] Flash, and she was down there jamming out. And not just being a spectator, but being engaged in the scene. Madonna's association with the dance music and the gay scene and the hip-hop scene merging in the downtown clubs in New York City, and her coming from Michigan, she got it.... And she knew Dre had something special. A song like "Where Life Begins" is right up his alley. She had a relationship with Dre for his rawness and realness. You gotta be around someone in this business who tells you, "No, I'm not digging that, that's why." And also keep the window open to listen. I think that's what Dre did.

Andre Betts: "Where Life Begins" was the first song we wrote on Erotica. I started working on the track and she started writing lyrics. She called me a few weeks before and asked me over the phone, "I'll be in New York in two weeks, do you want to work?" I'm like, "Yeah of course." She's like, "Find a studio, I don't want to work in a popular studio, I want to be low-key." [The studio I picked] was a hole in the wall for real. She came in, started writing, she's like, "What do you think about this direction and these lyrics?" I was like, "That sounds like something I'd write." Our session got interrupted because a big rat ran across the floor. I'm the only one that got the feet up so at first I didn't think she saw it, and she goes, "Dre, stop being a bitch, it's just a rat." [Laughs] She said, "I'm from Detroit, I'm not worried about a rat."

Shimkin: She really holds fast to a general rule, which is that she's in charge of lyrics and melody, and you're in charge of music. While she has her say in the music end, it's more about the arrangement and how it works with her vocal. She'll still be open to ideas you have about a vocal. One is her dominion, the other is yours, and they don't meet that often, but it's not unheard of to be able to comment either way.

Donna De Lory: She would completely just hear it in her head. Especially when we're doing vocals. Sometimes [backup singer] Niki [Haris] and I would be like, "How 'bout this? How 'bout that?" And she was like, "Nope, this is how it's going to be." And it ended up being great. She was open to other ideas, but I really respected that.

Wimbish: [My first day in the studio], she rolls up and she's got a box with these Playboy magazines from like the '60s. She comes in, Dre sees her and she's chilling, Dre's like, "Yo what's up Mo how you doing?" They start having a conversation. Dre says, "What do you got here in this box." Before she can say anything Dre takes one of the magazines and opens to the center section, is like, "Damn these old babes had some titties back then!" Dre's real straight up and down with her. She's Madonna, she's got that alpha female vibe -- and no disrespect. I'm like "yo, let me see that." She's like, "No, no, I don't want you to see anything 'til you play some bass." Our relationship was broken in based on Dre, that moment and Playboy magazines. Dre's looking at the centerfold, Madonna's doing her Madonna thing, saying, "no, no," and I'm like, "I'm not doing anything until I see some titties and ass."

Shimkin: I was 21, 22 years old at the time. While I'd worked on a lot of major artists' records and spoken to some of them, it can be intimidating at first. When we worked on "Vogue" I didn't speak to her that much, but when we started working in [Shep's] house [on Erotica] and you're there every day, you realize somebody is just who they are. One time, she was asking me if I was done on the computer. She asked me a few minutes later and I was like "not yet," and I started getting more nervous. The next time she asked me, I lost it and I thought it was the end of my career, I said, "I'm not done yet, make some fucking popcorn and I'll let you know when I'm ready." And she was like, "Ah-k." I think she appreciated someone not being a sycophant and kissing her ass, and just being real. It became much easier as time went on. I think she enjoys having people around her who allow themselves to be themselves. She's really no different than what she puts out there to the public in a movie like Truth or Dare. There's not a persona and she doesn't hide who she is.

The first single and title track, "Erotica," set the tone for her album and the Sex book (a Middle Eastern-flavored version entitled "Erotic" was included on a CD with copies of Sex). But unlike many of the other tracks on Erotica, "Erotica" underwent numerous radical changes during the album sessions.

Shep Pettibone: "Erotica" was four different songs throughout the process. She loved the groove. She would sing it one way, background vocals harmonies and all, then decide to erase everything and start over again. Every version was very good. Shame she made me erase stuff.

Shimkin: The original version of "Erotica" wasn't as slinky and sexy and grimy and dirty sounding until we were in the mixing process of the record, [which was] more toward the final stages. It was experimentation. When we realized it was going to be the first single and started working on the remix, it took on a different, darker vibe. That's when the character emerged, this Dita, when she ad-libbed the speaking parts. Then the character became something that took over.

Pettibone: At one point this was a finely tuned album. She scrapped that and wanted it dirty, murky and not polished.

De Lory: She was more grown up; she was more mature. She had her statements to make and you were there supporting her.

If "Erotica" was a bold sonic departure for Madonna, the second single, "Deeper and Deeper," found her in more familiar disco and house territory – it even featured a lyrical shout-out to her No. 1 hit "Vogue," which "Deeper and Deeper" producers Pettibone and Shimkin also worked on.

Shimkin: The music [for "Deeper and Deeper"] was fairly complete when we handed it to her, with the exception of the middle break bridge section, which took on this Spanish flamenco feel. It had the disco-y feel, the chorus and the melody was all intact, but when we were in the studio transferring the demo elements and adding new elements and getting ready for the mix, I was sitting on the couch in the control room with a guitar and started futzing around with the guitar line in the flamenco guitar section. And she was like, "Yeah, let's do that." Then Shep came up with the idea, "If we're going to go for it, let's go for it – let's add castanets and really take it there." It was an odd thing -- it's not what you normally think of doing in a disco song or club song. But it was a creative process and a lot of fun. [Ed. note: Originally, "Deeper and Deeper" was Shimkin's only credited co-write on the album; he's since been officially credited as co-writer on six other tracks.]

De Lory: All the records with her, you'd show up at the session and you just couldn't wait to hear what she was doing now. By then I'd gotten to know the fans really well, and I thought "the fans are going to love this," especially when we did "Deeper and Deeper." Niki and I loved those songs because we wanted to belt it out. We had so much fun. I remember the brilliance of her vocal arrangements, how she'd wait 'til the end to bring something new in, and you don't want it to fade out, but it is fading.

Shimkin: We were in the process of adding background vocals [to "Deeper and Deeper"]. Most of the vocals came from a Shure SM57 and a quarter inch tape from the demo session, but we did recut some of the vocals. And Shep, while recording, was singing the "Vogue" line over "Deeper and Deeper." She heard it and emulated it, and it just made it. It's happenstance when the melody and key of an original song meld with another one. I think Shep may have suggested [keeping the "Vogue" reference] as a joke and she did it, and we decided to keep it.

Pettibone: Yes [that's what happened].

For as dark as Erotica is, there's actually quite a bit of humor on it, from the cheeky "Vogue" shout-out to the ridiculously boastful "Did You Do It," a rap freestyle set to the music of another album track, "Waiting." It wasn't originally intended for the commercial LP, but it's the reason there are two different official versions of the album.

Betts: What happened with "Did You Do It" was, we used to snap on each other and make jokes. Madonna and I used to talk a lot of shit to each other – a lot. The guys used to always ask me, "the way you guys talk to each other, I know you guys are doing something." They would ask me, "did you do it? Did you have sex with her?" I'm like, "helllllll no." And they're like, "you're lying, you're lying." One day she had to go somewhere, and I'm almost finished with this record, I'm mixing "Waiting." While she was gone, I was just like, "what are we gonna do now?" Everybody's laughing because it's the song "Waiting" and we're waiting for her. And I said, "give me a mic, I'm going to freestyle something." And as a joke, I told them, "guys I need you to sing this part, yell, 'did you do it,' and I'll do the rest." So when she came back she was expecting to hear "Waiting," but I didn't know she was going to come back with the guys from the [Sex] book. So she comes back with four guys in suits, and the song is cued up, ready to play. So I told my engineer, "play," and he goes "uh, no man, this is not the time." And Madonna goes, "stop being a bitch, play the freaking song." He wouldn't do it, so I hit play and sat back down. I'm thinking, "man I don't know how this is going to go down, but it doesn't matter, I'm already paid and this is the last week." So this is going to be one of the worst jokes of all. When I hit play, man, she leaned over behind me and she literally had tears in her eyes and goes, "You are fucking crazy." Not long after that I was with Doug [Wimbish] in Massachusetts working on Living Colour's Stain album, she calls me and says, "Dre, I'm using that song on the album." I said "what? Hell no, I'm not a rapper, I didn't even write those lyrics, I just freestyled them," and she's like "I don't care, I think it's brilliant, I love it." Freddy DeMann [her manager] gets on and says, "What if we gave you 75/25?" And I said, "Shit, put that on the record. I don't care what I sound like now." [Laughs] That's really what happened.

Wimbish: Dre helped pave the road to making her explicit.

Betts: Then she called me back to blame my ass: "You know you're the reason I have to have an explicit sticker on my album." I was like, "okay, how you gonna blame me? You decided to put it on." I was like, "You guys want to go through all the trouble for this song to put two different records out?" Because Kmart wouldn't sell records with explicit stickers on them -- they wouldn't even put them in the store.

Erotica wasn't all libido and leather, though. The reflective, regretful "Bad Girl" is one of her most affecting lyrics, and "In This Life" is Madge at her most existential. Meanwhile, songs like "Bye Bye Baby" and "Why's It So Hard" find her experimenting with filtered vocals and reggae, respectively, and on her cover of Peggy Lee's "Fever," she marries chilly club music to a torch song of yesteryear. Taken together, the album shows Madonna's growing willingness to expand her horizons in terms of subject matter and studio techniques.

Shimkin: "Why's It So Hard" is really funny, because it was midpoint writing the record, and we were all a little burnt out. Everybody went on vacation, and Shep happened to go to Jamaica and I happened to go scuba diving in the Cayman Islands, and both places are heavily reggae-based culture. That's what we came back having listened to, so we decided out of nowhere to do a reggae track. And then my vocals appeared on it. Going to see the Girlie Show live and see my vocals lip synced and coming over the loudspeakers at Madison Square Garden was surreal for me.

De Lory: The song "In This Life" was very serious. It was just nice to go into the studio and share our own voices on that, which we could all relate to with what was going on, losing friends to AIDS.

Shimkin: "In This Life" had a really deep personal attachment to her, and [it has an] uncluttered nature to allow her vulnerability to come through. Obviously ["Bad Girl" was] a highly personal lyric. There's a raw element and simplicity that lends itself to a vulnerable vocal and lyric that she puts through. You really hear the emotion in her voice.

Pettibone: [I] never thought about [whether "Bad Girl" was autobiographical]. It was just a good song that I'm sure many people can relate to.

Shimkin: "Bye Bye Baby" was committed to tape with the filtered vocal – it wasn't an afterthought, it was how she heard herself when doing the song. We went to tape with that effect, there was no removing that. Sometimes you apply treatments like that in the mix, but that was committed to tape. There were no restrictions. Everything was tried that was wanted to be tried.

De Lory: When I heard "Bye Bye Baby" and that vocal effect, it had a lot of attitude. There's a bit of girl power in there and that attitude to be able to say that to a guy. You can hear how ahead of its time it was.

Shimkin: We had a song called "Goodbye to Innocence" but that turned into a cover of Peggy Lee's "Fever"; it was something that evolved with the project. There was a song called "Shame" and "You Are the One" [from the sessions that didn't make the album]. I think "You Are the One" fell into what "Thief of Hearts" was feel-wise, and "Shame" probably could have made the record, but it had a happier vibe, it was a little more playful, so I see why it didn't. But they're sitting there in the vaults somewhere. Maybe one day the Basement Tapes will be dug up. Some of it can be found online. People, I think, went into Library of Congress, played demo tapes and somehow copied them. Madonna has such a rabid fan base, they're so interested in knowing everything she does.

De Lory: Niki and I recently did a cover of "Rain," we both love that song and love singing it live [the two still record and perform together]. When I listen to those records I'm so proud of her for being so innovative and being fearless, and to be part of that was incredible. To be on a recording that will be around for as long as forever will be for us humans, I'm so proud. Niki and I were really taken care of, we were paid well and respected and had a great time with Tony and Shep, and I think that comes across on the records.

While Madonna's turn toward transgression wasn't apparent to everyone during the sessions, her collaborators eventually realized the through-line that connected Erotica, her Sex book and the erotic thriller Body of Evidence. At the very least, they were certainly aware of the controversy that engulfed the album upon its release.

Wimbish: She knew how to deliver with shock and awe. The industry had a flow, she got it, and I'm not brownnosing her.

Shimkin: I'm 99.9 percent certain she had this [overarching theme] envisioned ahead of time. It wasn't as obvious to us before when we were doing songs like "Rain" and "Bye Bye Baby" and "Why's It So Hard," but as it slowly came together, it became more obvious as we saw things alongside it. The Sex book, that was being worked on, and she was shooting the [Body of Evdience] movie with Willem Dafoe.

Pettibone: She kept the book very secret from me. It probably would have been a bigger album without all the controversy. But, after 25 years it still sounds good. Better than her newer albums actually. Whatever the matter, I'm still proud of it.

Wimbish: There's all this controversy going on. Here's the deal. From "Borderline" going on, she's a teenage pop idol. And now all the sudden them titties is out. Middle America and everybody else giving their daughters that $10 to buy that record are like, "hey, wait a minute…" Having a record come out with explicit can take sales away from a label. It's all bullshit. People start freaking out and people are starting to cockblock. It's a business we're in. Anybody sees a possibility to shut stuff down, and it starts in the industry itself. But you wouldn't have some of the lanes that are there now without her putting that record out. Fact.

For the book/album release party, Madonna doubled down on the BDSM imagery and threw an infamous party at Industria Superstudio that (to paraphrase Morrissey) would have made Caligula blush.

Betts: Walking in, just showing up out front, is Hulk Hogan standing there trying to get in. He eventually got in. I walk up with my dreads and about three four people, they look at me walk in, I look back at Hulk Hogan like "shit…he could probably whoop my ass." I'm thinking this will be regular party, whatever. The first thing I saw was a naked person suspended in the air on chains, and I say to myself, "oh shit, this will be one hell of a party."

Wimbish: That record launch party she had, oh my God, that was one of the best record release parties ever. By the time I got there it was way past full effect. She had folks behind glass, strippers, and she was like, "this is the way it's supposed to be done." This is no kissing and cuddling – I want to scare you. All y'all know what you're really doing behind closed doors, so let's get it on.

Betts: When I saw the sushi come by with two tits on the tray and the sushi surrounding the tits, I was like, "oh man." Then I saw this big tub of popcorn but the popcorn was moving because this naked woman was underneath the popcorn. I was like, "this is getting crazy now." My friend goes "what's all those doors over there?" So he looks in the first one and goes "oh shit Dre come here," and there's a girl playing with herself. And I go "wow, okay." So then he moves to the second one, there's a couple in there having sex. And he goes to the third one, and it's two guys. And he freaked the freak out, he's like, "oh shit! I've never seen that before." And there was two doors left and he goes "hell no, I don't know what I might see in those doors." The whole point of the party is you didn't know what you're going to see.

Wimbish: The record was one thing, but that party, in my opinion, changed the game.

Betts: She herself didn't do anything crazy that night. She was like, "I've had enough, I want to chill."

Erotica netted four top 40 hits on the Billboard Hot 100, including two top 10s ("Erotica" went to No. 3; "Deeper and Deeper" rose to No. 7), and hit No. 2 on the Billboard 200. It's sold 1.9 million copies to date, according to Nielsen. Even so, the album received mixed reviews, especially compared to the raves she got for Like A Prayer three years earlier. But Erotica has quietly grown in stature over the past quarter century, with critics and artists frequently citing it as a pivotal release in pop and one of her finest efforts. Perhaps the best postscript for Erotica comes from Madonna herself in this 1992 interview with MTV's Steve Blame: "A lot of the things I deal with in my music and the book are, in particular, with the repression that's going on in America right now.…There's a lot of really narrow-minded people. If I can change the way 1/100th of them thinks, then I've accomplished something."