In 1974, one of the most infamously grisly horror movies ever made was released to an unsuspecting but totally welcoming public. In the nearly 40 years that followed, The Texas Chain Saw Massacre only grew in popularity, and the stories surrounding its creation, as well as the belief that it was based on true events, have perpetuated to this very day. Someone has decided to clear up some of the myths and give the low-down, and who better than the man who is right at the center of the controversy: Gunnar Hansen, Leatherface himself, whose new book Chain Saw Confidential is in stores now. We spoke to the chainsaw wielder about the truth, the myths, and the legacy of one of horror cinema’s scariest films.

NERDIST: What prompted you to want to write this book?

GUNNAR HANSEN: It’s a book I thought about writing for a long time, and I’ve been on and off on the idea. I had been approached by a few publishers in the past, and, finally, I just thought this is the time to do it. I was able to think of the book in terms that made it a little bit bigger and more inclusive about film in general, and I just thought, four of the guys have died and I need to get this book written before our memories settled into jelly, before too many more of the people involved in the film are gone. That was really it; it sounds really grim, but if there was a time to do it, it’s right now.

N: The movie is still as big as it was at the time and new people are finding it all the time. Did you have any idea when you were making the movie that it was going to be such a big cultural touchstone?

GH: I don’t think so. I think all of us had some hope for the movie, but I don’t think any of us had any concept of what would happen with the film. My hope was, I would think to myself: how do I measure this movie, what am I going to think, what has to happen before this movie is a huge success for me, and I thought, if five years down the road, a few hardcore fans remember it, wouldn’t that be great? And that was the dream, and that was as big as I could imagine for this movie. I think all of us felt that way, all of us felt like, we hope something comes of this, but we had no idea.

N: As you talk about in the book, the legend behind the making of the movie is as notorious as the movie itself. What’s been the most enduring myth or your favorite false rumor people keep bringing up to you?

GH: I think what comes up constantly is how many people are convinced this actually happened. That is the most consistent storyline from the myth of Chainsaw Massacre. And what’s interesting about it is, a lot of people, when you say, no, it didn’t happen, they’re kind of relieved, but many people become extremely angry and they say you’re wrong, you don’t know what you’re talking or they say—as it says in the book—they say that denying the Chainsaw Massacre is like denying the Holocaust. Some people are so invested, emotionally, in the movie, and I think that was the biggest surprise and the strangest phenomenon.

N: There have been a fair amount of rumors about you specifically — you mention it in the introduction to the book — that you were this shy person who they slapped a mask on and made you do these things, which I’m sure you find hysterical…

GH: I love this thing that Marilyn [Burns, who played Sally, the movie’s heroine] had said; She was told that I was this poor poetic soul who is damaged terribly, psychologically damaged terribly by my experience with Leatherface.

N: What were your experiences like on the set? What was it like for you filming Texas Chainsaw Massacre?

GH: First of all, I was always so separate from the character; there were no issues like that. People say, “Did you have nightmares? Well, no, I didn’t have nightmares; I was just working on a movie. There was no real burden psychologically from the film for me. I thought it was a very interesting job. I always felt like myself, except for that one moment when I temporarily forgot myself and thought I was Leatherface. Otherwise, I kept myself very separate. The difficult part of the movie was that, physically, it was so demanding. There was this chase scene in the middle of the summer, in the middle of night where I couldn’t see out of my mask, and that scene took forever to shoot. Just generally, the demand of doing a movie where you’re shooting 12 or 16 hours a day, seven days a week and it’s 100 degrees — I think that was the worst part for me. It was just a grueling shoot. Marilyn Burns said, when she finished the shoot — when we finished the shoot — she ran home, climbed in the bathtub, and just cried for two days. I think that’s how everybody felt. Leatherface doesn’t cry, but still.

N: Toward the end of the movie, there’s that famous dinner table scene which a lot of people have pointed out as being — you can almost see the actors going nuts on screen there. Was that as intense a scene to film as it came across on screen?

GH: It was. First because we already had been shooting so long, so coming into that scene, we were all really on the edge of running out anyway. That scene, as hot as they were in that scene, was probably — If it was 100 degrees outside, shooting that was probably 120-125 degrees. We were in the house with the windows covered and no air moving and all the lights on. So we were already tired, and then you add the fact that we shot 26 hours without stopping, it really broke us, in the sense that at that point we all just wanted to crawl away. Certainly, it was brutal for Marilyn, because she was very frightened in a couple different shots there, and she said it’s not a snuff movie — snuff movies were a thing at the time — why I kept wondering, I know this isn’t real but is this a snuff movie? So she was really frightened, and all of us were burned out at the end of that, and that was when finally, at the end of that scene, I finally lost any sense that I was in a movie, just for an instant I thought I was Leatherface and I thought I was supposed to kill her. That was a very uncomfortable moment for me when I realized that this just happened, and I hope I never have that happen again.

N: What was Tobe Hooper like as a director during all of this? I’m sure he was just focused on getting the scene shot but what kind of atmosphere did he create?

GH: He was fine; it was an intense atmosphere, but there was no drama from Tobe. Tobe gave us a lot of room, he let us play the character as we wanted to play, which is what every actor loves. He was very focused on the mechanics of the shooting, long discussions on exactly how they were going to light the shot, and very careful rehearsals of the scenes, because some of the camera work was tough, and to get every shot, the dollying we did and movement of the camera, he took rehearsal after rehearsal after rehearsal to get the timing of the actors exact because you’re trying to coordinate this moving scene with a moving camera and that slowed the shooting down. That was really the atmosphere where everybody was very focused and working very hard to get it exactly right. I think if he had been a tyrant on the set, it would have made it impossible, but he never was, he always was very low key and relaxed.

N: What do you think it is about the character of Leatherface that has stuck with people so much? What do you think about the character himself that has become so iconic?

GH: I think part of it is because he’s an ambiguous character. When you have a character like a monster, which in some way Leatherface is the monster, when the monster is purely evil, he’s essentially uninteresting because you’ve got him figured out. Leatherface and the rest of the family, they’re very ambiguous in terms of the evil, because you can see them as the monsters and the killers, but they’re also, at another level from another point of view, the victims, because they’re the ones who are intruded upon. They’re the ones who are engaged by the kids. I think because of that ambiguity, which is really expressed when Leatherface kills Jerry, the van driver, and Leatherface runs to the window and finally sits down and frets. That scene is your glimpse into this heart and humility of the character: he’s worried. I think that is the point at which some of the audience develop some kind of sympathy for him, and I think that’s the key to why he’s such an appealing character and why people are so interested in him.

N: What do you think of some of the other portrayals of Leatherface from the other films? Do you think any of the actors have nailed what you thought the character was?

GH: It’s a hard question to answer because I understand, and every actor that plays Leatherface has two tremendous disadvantages that I didn’t have. One is that the writer of each subsequent film has a different concept of Leatherface, so he’s written in a different way. At the same time, each actor is different physically so there’s no duplicating the Leatherface that I created, because what they wrote is a different character; and two, these guys are different physical people — their build, their whole physical being is different, it’s an impossible task to become Leatherface as he was in the first movie. I never criticize or felt any criticism of any of the other Leatherfaces, because I felt like they created their own Leatherface that works for that film. In fact, most of the Leatherfaces that followed I’ve become friends with. Just last night, I had drinks with Dan Yeager, who plays Leatherface in Chainsaw 3D.

N: Writing this book, compiling everything, what has been your biggest revelation about the film, maybe something you didn’t realize at the time or something you forgot until you were putting all this together?

GH: I think the thing that surprised me the most was from Marilyn. It was hard on her to shoot the film, but I don’t think I had any real clue, until I interviewed her that night, the kind of suffering she went through and how brutal the filming was on her. I think that was the biggest surprise to me, and I wonder, looking back, how did she survive psychologically, because of the level of brutality that she suffered.

N: And finally what are you excited for fans to get out of this book when they read it?

GH: I think one is them hoping that they’ll get a new perspective on Chainsaw. They’ll understand what about the Chainsaw stories are really myth and what about the Chainsaw story is true, and they’ll get a better sense of truth or lack of it behind the film and a better sense of, perhaps, where Chainsaw sits within horror, because that’s what the book really discusses: what is horror and how does Chainsaw meet what we think horror is? I’m hoping that’ll help them focus their own thoughts on how Chainsaw plays and what Chainsaw Massacre is about. I also write an interpretation of the film, like what is the film about. To me the film is about this, and I say it can be about any number of things, and with this, you can support your theory by looking at the film stuff, but here’s one perspective on what this film might be about.

Read the rest of the story of the most infamous horror movie of all time in Chainsaw Confidential, in stores now.