When Ashleigh Ball landed the voice-over roles of Rainbow Dash and Applejack on Hasbro’s “My Little Pony” reboot back in 2010, she never dreamed the majority of her die-hard fans would be grown men.

“In today’s world, we are so quick to judge people, and I was for sure. You see a guy that’s wearing a pony outfit and you’re like ‘That’s weird. I don’t know about that. That makes me uncomfortable,’” Ball told FOX411, describing her first interaction with the Brony community.

She told her friend, filmmaker Brent Hodge, about the emails she was receiving from adult male fans, and he quickly decided it was a phenomenon he needed to document.

In “A Brony Tale,” which premiered at the Tribeca Film Festival on Saturday, he gives Bronies a chance to explain why they have fallen so hard for a show that’s intended target audience is little girls.

Today, Hodge said he’s heard there could be up to 3 million Bronies around the world. They range in age from 14 to 57. He also said 85 percent of Bronies are male and 84 percent are straight.

“You think these guys are just weird, and we were definitely creeped out at the start and scared as well, but as we kept going [with] the film it just started getting normal,” Hodge said.

Dedicated Bronies don’t just watch the latest episodes of “My Little Pony.” Most have a strong online presence in the Brony community —or fandom— and many collect memorabilia and attend Brony conventions, such as BronyCon, which is featured in Hodge’s documentary.

Some Brony fans have even taken to attending concerts that Ball’s band, Hey Ocean, puts on.

“They started to kind of follow the music I was making, and they would come to shows with my band and show up in pony costumes and with little plushies on them and wanting me to sign their merchandise," he said. "I knew that there were fans like this because people that I know had done Anime, but this kind of series was intended for a younger audience so it was a big shocker.”

Dr. Marsha Howze Redden, who has been studying Bronies for two and a half years, said many Bronies hide their obsession with the show from their families and friends.

At a Brony convention, she and her research partner participated in a panel discussion in front of a crowd of “My Little Pony” enthusiasts.

“We said ‘How many of you have families that think you’re somewhere else?’ and a lot of them just applauded,” she said. “We had a number of Mormon Bronies come up to us and say ‘Look, how do I tell my family about this?’”

One man named Steven described his experience shopping for “My Little Pony” merchandise in the documentary.

“Just me standing in the aisle to begin with, there might be a mom and her daughter walking by, look down this aisle and see an older guy looking through pony toys. It’s programmed in their mind to jump to the worst-case scenario, which might be, you know, ‘Oh, he’s a pedophile or he’s a big old man child or something is wrong with him.’”

But the Bronies are harmless, Ball insists.

“[They’re] weird yes, for sure weird, and like different, and like some of these people… they’re maybe not as accustomed to socializing as maybe someone like me, but I don’t feel scared ever,” she said. “They’re really friendly, lovely people.”

Dr. Redden said some Bronies may suffer from social awkwardness.

“We have some anecdotal evidence that there is a higher percentage of anxiety and Asperger’s in this population than there is in the general population,” she said.

But she insisted the majority do not have social issues. They just like a show that was intended for little girls. A lot.

In the film, many of the Bronies interviewed are adamant that it’s the series’ good morals and good writing that keep them coming back for more.

“Don’t think of it as six little ponies in ponyville,” one Brony implores. “Think of it as six friends learning from each other.”

Veteran Brian says the show helped him get through tough times when he returned from Iraq. He’s part of a large group of military Bronies.

“Princess Celestia is amazing… Of all the characters on the show, that’s the one I’ve come to admire the most. She’s lived a thousand years and it feels like it…” he tells the camera passionately. “Any adult, who has really gone through it all and been really thoughtful and really caring and anything like that, is going to be a Princess Celestia.”

Ball said she can see why adults watch the show, calling it “a really well-made” show.

“It’s not as cutesy as the [original ‘80s] ‘My Little Pony’ series.”

Both Ball and Hodge insist if there is anything they’ve concluded about the Brony community, it’s that being Brony is about more than liking the series.

“It’s about the community, friendship and the morals they get out of the show,” Hodge said.

Ball added that the Brony fan sites give like-minded people a chance to find each other.

“A lot of these people, their lives are changed by this movement,” she said. “They found each other through this fandom. They maybe don’t feel comfortable in normal social settings and they’ve found other people like them that they can connect with on a social level... Overall, it’s a really positive thing."