Upon one of her usual visits to her mother’s house in Japan, Kyoto Miyake heard a breaking news alert from the other room and immediately looked up from what she was doing.

“I was like, ‘What is it? Is it North Korea or Syria?’ No, it’s about this girl leaving AKB,” Miyake says of discovering just how big idol culture had become — singing, dancing groups of young women, ranging in age from prepubescent girls to young women in their early 20s, of which the 130-member-plus AKB is the nation’s most famous — in the years since she decamped for England to study film. “That’s the national news that everybody was talking about.

Having previously studied the history of witchcraft at Oxford, Miyake had seen what it looked like when people had fallen under a spell, but nothing quite like this as she watched cultural commentators speak about which girls would be retained by AKB during their annual elections with the same import as they would about who will become the next prime minister of Japan. Still, feeling the full weight of the patriarchal society growing up, it felt eerily familiar personally.

“When I grew up as a girl in Japan, I always felt quite awkward and clumsy and very strange because whenever I was not being or acting cute enough, it was taken as a sign of defiance or offense,” she recalls. “I was quite confused and after I left when I was 26, I realized things didn’t have to be that way for me, so I decided not to return. But I keep going back to Japan several times a year, and I would read Asahi Shinbum, which is like the New York Times, [where] every year they have a series of articles and predictions for the AKB election. It brought back all the memories of feeling awkward. It felt like it represented everything about being uncomfortable as a woman in Japan, so I wanted to explore it.”

“Tokyo Idols,” the exhilarating result of that exploration, initially will cause your jaw to drop as it did to Miyake in observing the considerably older men that make up the bulk of the fans of the young female idols, unabashedly convening at concerts where they echo every lyric and writhe to the music as if it were a spiritual experience, spending every free moment they have outside the gigs and their professional lives plotting out ways to boost the popularity of their favorite artist as part of fan clubs. However, it is Miyake’s meticulous and engaging investigation into the perfect storm of socioeconomic conditions have given rise to the popularity of the subculture that is truly unbelievable, illustrating how a billion-dollar industry has grown out of a society devastated by a prolonged recession where salarymen have been emasculated by their ability to provide for another and have instead opted to throw themselves into responsibility-free relationships where they feel as if they can claim emotional superiority in being physically, if not necessarily psychologically, more mature than their object of desire.

Over two years, Miyake surveyed nearly everyone from 10-year-old idol aspirants to sociologists to capture a full picture of the cultural phenomenon, but “Tokyo Idols” centers primarily on Rio, a rare solo idol act who made it out of a humble hometown in Chiba year nearing her 21st birthday is getting perilously close to growing out of her prime, and perhaps her biggest fan in the 43-year-old Koji, a charter member in her fan club the Rio Brothers who once spent 700 hours going to her concerts in the year following the breakup with his last girlfriend. At once a deliriously entertaining portrait of obsession that doesn’t trivialize how unhealthy it can be, “Tokyo Idols” is worth going crazy over and in the midst of a busy Sundance Film Festival where the film made its world premiere, the filmmaker spoke about overcoming her own prejudices to get inside the minds of her subjects, how she connected the idol phenomenon in Japan to a growing feeling of isolation around the globe and how her personal experience informed the film.

A scene from Kyoko Miyake's "Tokyo Idols"If your inspiration to make this film came from growing up as a young woman in Japan, was it interesting to explore this from the perspective of middle-aged men?

Initially, our plan was to focus on a few girls and follow their career trajectory — maybe find three girls at the beginning, middle and end of their career, but we realized that to tell their story, we also need to look at the men who are supporting them. It took me awhile because I went in with many preconceptions towards these men and it was much easier for me to sympathize with the girls because I’m a product of the system. I know how early you internalize that idea that you need to please men all the time to achieve anything. So at the beginning, I found the men creepy and I was in my mind saying [about them], “Just grow up and face women of your age” because these men are my age. I have lots of girlfriends of my age still living in Tokyo, but I don’t have many male friends and I know that most of my girlfriends don’t think idol culture is a good thing, but they don’t have any strong opinions. They just try to ignore it and I was also like that. But as I got to spend more time with them and know them better, I began to understand a little bit better where their anxiety or their loneliness comes from — they belong to the same generation [as I do]. We share the same disappointments and disillusionment and disenfranchisement, so that was one discovery for me and also that brought a change to the story and the film ended up as much about the fans as about the girls as we made the film.

You make the point that idol culture is no longer something that these men are ashamed of, publicly showing their affection for these young women and attending their concerts – it’s out in the open and mainstream. Does that make it easy to get a superfan like Koji on camera?

In general, even the nine-year-olds and 14-year-old fans of these girls, are considered slightly strange, even in Japan. They know that they have to somehow hide their fascination. But if you’re supporting a girl like Rio, who’s not really girly – to Japanese standards, she’s strong, independent and bossy, so her fans tend to have less romantic feelings towards her than towards other idol singers. Koji was helpful for us, partly because he wanted to support Rio and he thought this film might help her — and he’s certainly not hiding it — but also he’s [around] my age, so we could have a chat about many things. Maybe some people draw parallels to strip tease [in the U.S. with idol performers], but the difference is that this is not something that’s frowned upon. Girls don’t have to hide it when they stop being an idol. It’s not stigmatizing, so rather than asking myself why are they doing this, I wanted to find out why this is so accepted socially.

Visually, you’re able to convey so much with the way you shoot the exteriors of Tokyo and contrast them with what goes on indoors. How did you go about shooting those city scenes?

The idea of those outdoor shots was to capture the loneliness because I was once one of those commuters walking in that anonymous, nameless crowd commuting on the packed train and I know how lonely you can feel while being surrounded by millions of people. So I wanted to imagine what each one of them might be feeling. It also helped to have a Canadian cameraman [Van Royko] because for the Japanese, it’s such familiar sights that they would [think] what’s the point? But because we had a foreign cameraman, he went in and captured something I didn’t expect him to catch, so that was really a nice surprise.

A scene from Kyoko Miyake's "Tokyo Idols"How did Rio become the main girl you followed?

We contacted both known and unknown bands and it quickly became clear that known bands would only allow us to film them when they had perfect makeup on and a publicist on the side. We’d have to submit a list of questions in advance – that’s how they deal with TV reportage, and because a documentary like this doesn’t really exist in Japan, they weren’t as open and they were quite restrictive, so we started to cover underground idol scenes.

Once we were in this literal underground bar that was really dingy. Usually idol concerts last for two hours and consist of 10 idol bands [where] each of them would have 10-minute slots. We were there to film another band, but we saw Rio. We only got permission to follow this one band, and we weren’t allowed to talk to her. But [I saw these] these fans of Rio — these men — are crazy, and we couldn’t talk to them [either, so] we were starting to pack our gear and Rio actually came to us and said, “My name is Rio Hiiragi and if you are interested in talking to me, please contact us” and then she looked around and the manager came running. He gave us his business card and Rio is like, “Where’s the brochure? Where’s the new poster?” And she was upset he didn’t bring the whole package. I just loved the way she bossed him around and I thought “Oh, this is our girl.” She’s very independent, she’s a business woman. It wasn’t only the manager deciding what he could do with Rio, but Rio and the manager [making decisions together] so it felt more comfortable. She’s also from Chiba and I’m from Chiba, so I understand the desperation to get out of [there].

Structurally, the film is very easy to take in, but quite complex in how you keep looping back to Rio’s story as you go deeper and deeper into the root issues in Japanese society that have created idol culture to rise. Was it challenging to find all the connections?

It was very difficult to structure, partly because to tell a story of what’s happening in the idol scene through what’s happening to somebody who’s not the most typical idol girl was a challenge. Rio is a solo singer, she only has one manager and he’s just a one-man band, and the Rio fans seem to really have this paternal feeling towards her at the same time as some romantic feelings, so they’re not the most typical bunch. We had to insert different story blocks, like points brought in by other girls and fans and experts. It was also helpful that our editor [Anna Price] was British, so she had incredible sensibilities and curiosity, and discussing and debating with her was for me really helpful to not only tease out the story and to structure it, but also to tell that story in the clearest way because I couldn’t take anything for granted. Finding that structure was probably one of the most difficult parts.

Were the sociologists and journalists onboard from the start?

There was a lot of back and forth in the edit. At one point, many people we showed the rough cut to said, “Oh you’re too lenient to these men,” but at another point we were told, “This feminist [journalist] is too harsh,” so to strike that balance was quite hard. But it was really rewarding for me to talk to her because she’s one of the few feminist voices of our generation in Japan, and in our generation, it feels like we are looking away from each other. There’s so many people who are living alone who are not looking for a partner. I’m not saying that they should get married, but it just feels like they are not talking to each other, so I just wanted to look at where that disconnection comes from.

A scene from Kyoko Miyake's "Tokyo Idols"Not in a romantic sense, but I wondered do the men who gather together as idol fans actually find that connection with each other?

In a way, it’s a virtual romance [with the idol], but what’s as important is to have this peer group and this sense of community, a sense of belonging. The Rio brothers meet up like four or five times a week and they have dinner or drinks together and what’s interesting is that quite often, they don’t know each other’s real names. They just go by their online names and some of them don’t reveal what they do during the day, so it’s like [having] an alter ego. Maybe between 9 and 5, they have this boring job, but when they leave the office for a concert with Rio, the brothers are in a different world. I keep using the word “fantasy,” for lack of a better word, but really I’m hesitant to use the word because it’s real. They are real people connecting with each other and Rio knows them, but it’s quite a homosocial atmosphere. Even if there are female fans, often they are given a special area at a concert and it looks like [the male fans] are treating women well, but it also looks like they want to keep to themselves and do these rhythms in unison [as they’re] being told that you are okay the way you are in all those Rio songs, so here’s a real sense of belonging which shows the loneliness they might feel outside idol world.

Was there a particularly crazy day of filming on this? It seemed like there might be a few out of body experiences.

Where can I begin? When I started to cover [the girl group] Amorecarina, some of the girls were nine and the other half were 12 or 13 and they were much taller than the nine-year-olds, so at the meet and greet, they would be standing up. All the men would be queueing for the little ones and the 13-year-olds looked kind of bored and unpopular and I was wondering how it would be to be 13 and feel too old. That was one of the heartbreaking moments. But there were a lot of moments that made me puzzled or bewildered. Like during the songs, [the idol singers] do little talks, a little bit like standup comedians – they’re only 15 or 16, they’ve only lived life for 15 years. Their jokes are so utterly unfunny. It’s like high school girls talking about things that they find funny, but nobody else does but all these men of my age, like 40 or 50 year olds, they are laughing their head off at these utterly unfunny jokes. And I was like who are these people? That made me think for a long time. There were many moments that surprised me.

What’s Sundance been like for you?

It’s been absolutely mad, but in a good way. This is my first festival experience, and I always wanted to premiere this film at a festival that shows documentaries and fiction to the same crowd. The audience has been young and energetic and it’s been great and exhausting. I’m so happy that people watch this film with an open mind. I really do hope the audience, even if they think at the beginning, “Oh this is crazy Japan,” towards the end of the film, they see parallels with what’s happening here — this urge to be instantly famous, justifying the objectification of young girls, and there are so many people living alone. In Japan, it’s both really ahead and really behind at the same time. There’s a huge market now for people living alone and focusing on what they want to do now rather than saving up and maybe building a family or buying a house or a car. If you go into convenience stores, there’s so much that’s just for one person and I think it is connected to lower birth rate and sexlessness and all these things, so if the film could somehow get this kind of discussion going, I’d be really happy.

“Tokyo Idols” does not yet have U.S. distribution.