The medical community had no clue how to handle medical doctor John Brinkley.

That’s because Brinkley wasn’t a real doctor but a quack and a con artist who, for a period in the 1920s and ’30s, created a nationwide craze for a bogus impotence cure. He peddled a “miracle” operation in which he sewed goat testicular glands into a patient’s scrotum.

The medically useless procedure turned Brinkley into a millionaire. His money let him launch the world’s most powerful radio station in Mexico, out of the reach of regulators in the United States. It also gave him a large enough following to nearly win the governorship of Kansas.

The new documentary Nuts! charts Brinkley’s rise and fall, including the American Medical Association’s dogged efforts to expose him as a quack and a climactic 1939 libel trial that proved to be his downfall.

In the film, director Penny Lane employs an unusual approach for the medium, telling the story through animated reenactments. Speaking from her home in New York, Lane talked about what Brinkley was actually doing to his patients, how he gave way to an entire counterculture on Mexican radio, and why we are so susceptible to frauds, even today.

You describe your film as “mostly true,” which seems like a very Brinkley-esque thing to say. What was mostly true about it?

[Laughs] Well, there was a man and his name was John Brinkley. He did claim to have found the cure for impotence in goat testicles. He did run for governor of Kansas and apparently had the election stolen from him. He did build the world’s most powerful radio station in Mexico. The big-picture stuff is all true. What gets tricky is the way the story is told, the perspective, the emphasis, and a lot of the smaller details.

For a good portion of the film, the story is told the way he preferred to tell it. One way to tell his story as a doctor is to say he was a little guy out in small-town Kansas, and he had this innovative idea to cure impotence with goat testicles, and he did it and a lot of people really liked it and said it worked, and then the powers that be came after him and shut him down out of professional jealousy. And it is true that the American Medical Association is the establishment, and quite conservative, and sometimes they shut down alternative practitioners for maybe less than noble reasons. But it’s also true that his “cure” did not work, and the AMA has an interest in protecting the American public from quacks, which he is.

The first story I told you is mostly true, but the meaning of it is totally manipulative. The purpose of telling you that story the first way was to make you sympathize with John Brinkley, and then I make you sympathize with and root for the AMA.

Brinkley comes to the tiny town of Milford, Kansas, in 1918, with a degree from Eclectic Medical University to open his medical practice. Is Kansas, to him, just a place for easy marks?

I think that he could find easy marks anywhere, and he knew that town needed a doctor. That was the era of the “country doctor”—every little town needed to have one doctor. So as the story that he tells goes, he just saw an ad that they needed a doctor in Milford and went there for that reason. He could’ve gone anywhere.

What was his thing with goats? Why were they the hook of his revolutionary procedure?

I think that he would say he observed goats in their barnyard state, and that they were the healthiest animal. That was his claim. That seems unlikely. More likely, he chose goats because we have this association with them that makes us think about sex. We’ve always thought about goats as being randy, or in ancient mythology we have Pan, half man, half goat. So I think it’s more about our mental associations with the goat and nothing to do with the physiological whatsoever.

You diagram in the film why the goat gland procedure is medically useless. What was Brinkley actually doing in these operations?

He did different things over time, and he made different claims about it over time. He [generally] took the gland of a very young goat, like a six-week-old goat, so a very small gland—it was the size of a macadamia nut. And then he would make an incision in the man’s scrotum and he would insert the goat testicle just under the layers of his skin. Not in there, just under the skin. And then sew it up. He claimed he was doing a lot more things—that he was hooking up blood vessels, and that the goat testicle lived on in the human body. But he wasn’t doing that at all. So he just kind of stuck it in there under the skin, and if you were the patient, you could feel there was something in there. And if the surgery worked at all, that was the secret to it: that you knew you’d had it, and you were told that it worked. It was the power of suggestion.

What was Brinkley doing with his “border blaster” radio in Mexico?

His rationale for going to Mexico was that he had his radio license taken away from him, and he had to say it was taken away from him for reasons of snobbery and professional jealousy and general fuddy-duddiness. His station in Kansas was very popular—it was the most popular station in America. So he loses his license, and one of his quotes, which is not in the film, was, “Radio waves pay no attention to lines on a map.” So it doesn’t matter if you’re in Mexico if you can get out of the reach of the U.S. regulatory system and do the exact same thing you’re doing in the U.S.

It seems like he had this idea first, and again this is a little tough to verify. But at the same time or shortly thereafter, a lot of people had the same idea. If he hadn’t done it, someone else would have. There was this whole era of what we now call border radio, all these crazy things ranging from country music to selling products you weren’t allowed to sell in the U.S. because they were deemed fraudulent. It was kind of the Wild West of radio.

The American Medical Association attempted to expose Brinkley’s quackery, and initially no one took them seriously. They were seen as this stuffy, conservative old boys’ club. Why is that?

At that time, there was no mainstream medicine yet. In a sense, the AMA created mainstream medicine in the U.S. There were a bunch of rival and competing medical schools and ideologies: You had the homeopaths and the herbalists and the chiropractors and the osteopaths. The AMA was really just another one of those competing forces for a long time. Over the course of Brinkley’s career, they ascended to what they are now. It’s in part because they shut down people like Brinkley that they became so influential.

The animation style really highlights the eccentric nature of the story. When you animate a documentary, do you have to treat it like a fiction film, or are there different rules at play?

That’s a really good question. I don’t know what rules were at play. [Laughs] Me and my writer, Thom Stylinski, we would say, “Wait, can we do this? Is it a documentary?” And we had to talk it out one decision at a time. The reenactment scenes are made just like anyone would make a fiction film. You wrote a script. A lot of the material is based on real things, so there’s a transcript—maybe a trial scene, or from Brinkley’s biography. But we gave ourselves permission to do whatever it took to make the movie work, in terms of fictionalizing it in our imaginations.

Brinkley became this folk hero entirely built on lies. Do you think his story is more about the depths one man can sink to, or more about the gullibility of the public?

I think it’s much more the latter. I can’t really explain his psychology—the film doesn’t attempt to. It really is left open-ended in terms of why he did these things. But as far as the latter thing, that was my interesting beginning. Why do people believe the things that they believe, especially when some of these things are so, I don’t know, crazy? [Laughs] The question for me was much more about why people believe what they believe, and how do they convince people to believe things that seem unbelievable. And are we any smarter today than we were a hundred years ago? For me the answer is emphatically no, not at all.

Do you think he did any good for anybody, even inadvertently, when all was said and done?

Yeah, I think so. I think a lot of people, especially inventors and businessmen-types, do a lot of good for the world even if they’re acting completely self-serving. He made the world more interesting—that’s kind of a flip way of putting it, because he also hurt people. He also innovated a number of things, particularly in broadcasting, that changed the world for the better. So he’s a mixed bag, like a lot of people.

But I’m certain there were many people who had him as a doctor, who felt that they had a good doctor, who felt they had been healed or felt that they had been treated well or taken seriously when some other doctor didn’t take them seriously. He wouldn’t have been so popular if people didn’t like him. It couldn’t all have been fake, because you couldn’t get very far faking everything.

This interview has been condensed and edited.

Andrew Lapin is a film critic and journalist who has written for NPR, Vulture, the Washington Post, the Atlantic, and many other publications. Follow him on Twitter.