In the summer of 2006, YouTube was only a year old, and people were very concerned for the safety of its breakout star. Only they didn't actually know who or where she was -- or whether she was even real.

Bree, the unassuming 16-year-old vlogger best known by her username, Lonelygirl15, was possibly a victim and possibly a hoax, but it didn't matter either way to the thousands of fans who anxiously waited for her updates. 

Not knowing was the real thrill. And 10 years later, Lonelygirl15's legacy is the currency of uncertainty.

Bree's first vlog appeared on the site on June 16, 2006 and was titled "First Blog/Dorkiness Prevails." In it, she offers shoutouts to her YouTube heroes, laments her boring life and positions herself as an outsider desperate to fit in.

"Well, I guess a video blog is about me. My name is Bree. I'm 16. Ummmm... I don't really want to tell you where I live, because you could like, stalk me," she says, scrunching up her nose before stopping the video for a second to the soundtrack of Psycho. 

Bree makes silly faces and directs her words as much to her knees as to the camera. She preemptively apologizes for awkward behavior, which mostly seems to involve not being sure what do in front of the webcam she invited into her world. 

She becomes more comfortable in subsequent videos, unveiling her world with a distinct goofiness regardless of the subject matter, which ranges from a childhood lazy eye as a metaphor for parents who just don't understand, to her favorite quotes from the physicist Richard Feynman, to why she still talks to her stuffed animals. ("They're someone that you can talk to when the real world lets you down," Bree says.)

The only other character in the original Lonelygirl15 videos (besides a plush monkey and Bree's offscreen parents) is Daniel, her only friend whose crush on Bree is unreturned. He dutifully edits the videos, but mostly lurks in the background. 

Vlogging is a cottage industries these days -- videos of teenagers making breakfast can get millions of views and lead to brand ambassador gigs and makeup lines -- but at the time, in YouTube's toddlerhood, Lonelygirl15 seemed to appear out of nowhere. 

Sure, Bree wasn't the only girl broadcasting life's mundanities, but she was the most compelling. Lonelygirl15 quickly became the most subscribed-to channel on YouTube -- in part because fans began to suspect something was amiss. 

In entries like "Me, Religion, and Daniel," "A Change in My Life" and "The Ceremony is Tomorrow," Bree, who previously dropped hints about about her religious background in vague terms, begins discussing religious camps and fighting with Daniel on camera about her faith, which he calls "weird." We see Bree preparing for a ceremony associated with her unnamed religion, which requires her to lose weight and receive weekly shots. She begins appearing on the show with gauze on her arms, and we will later learn her blood is being harvested. 

Things also became increasingly bizarre from a technical standpoint. Bree allegedly lived "100 miles from a mall," but fans noticed indicators that the vlogs were produced in Los Angeles. On the two occasions Bree left her bedroom, the plant life was consistent with what you'd find in L.A. Background music from local bands that hadn't broken out of the area didn't help either. Most obvious were the lighting and editing, which just seemed too professional. 

What's more, Bree's rising celebrity profile wasn't addressed at all in the vlogs, leading fans to suspect that the videos had been shot en masse, slickly edited and then released serially as if it was all going down in real time. But that only made things better.

"I like the community aspect of the mystery -- getting together and trying to figure it out," Riana Giammarco, who ran a Lonelygirl15 fan forum, told the Los Angeles Timesbefore Bree's true identity was revealed. "Though I would still watch if there weren't a mystery, the videos wouldn't appeal to me as much."

On Sept. 8, some three months after Lonelygirl15's debut, the Timesalso reported that a domain name and trademark for Lonelygirl15 had been registered even before the first video was uploaded, confirming that the vlogs were a calculated hoax. But the question of Bree's true identity -- and the point of the whole charade -- remained a mystery.

In April 2016, nearly a decade after Bree first appeared, Beyoncé played on a similar fascination with the line between fact and fiction when she released Lemonade -- what appeared to be a ruthlessly personal masterpiece, an unfiltered look at the cracks in her seemingly perfect life.

The Bey Hive and casual fans alike unpacked the visual album's meaning -- and potential autobiographical nature -- on their Twitter timelines during the HBO premiere. As her masterpiece unfurled, many genuinely could not tell whether this was just entertainment or the divorce announcement of the ages, with Queen Bey in the role of Henry XVIII orchestrating Jay-Z's pop execution. 

In the days and Becky Trials that followed, the verses of Lemonadewere accepted as fact, but soon, the lines began to blur. We were all reminded that not only is there room for delicious uncertainty, but the mystery tastes even sweeter. 

So the theories piled up. Becky is not one person, but a type of person. The antagonist of the album is not Beyoncé's husband, but her country. Jay and Bey are f*cking with you and cashing in on years of rumors about their relationship in the process.

Beyoncé's hyper-secretive nature added another layer of allure to the work -- she was simply not going to sit down for an interview and spell things out for us, so the challenge was on.

Then, of course, there was MTV's reality show, The Hills, a show that also just celebrated its 10-year anniversary. Debuting just weeks before Lonelygirl15, The Hillsmasterfully played on its tenuous relationship with reality -- so much so that everyone involved is still arguing about what actuallywent down in Lauren Conrad's mid-2000s Los Angeles.

In what was certainly the second best closing sequence in a television show after Six Feet Under, Kristin Cavallari tearfully bids Brody Jenner goodbye in The Hillsseries finale -- just before the Hollywood sign behind him is pulled away, revealing they have been on a set the whole time. 

The case of Lonelygirl15's real identity was eventually cracked by an actual teenager, of course. Eighteen-year-old Matt Foremski figured out that Bree looked exactly like a 19-year-old aspiring actress living in Los Angeles by way of New Zealand. Her name: Jessica Rose. Foremski's dad then broke the story on Silicon Valley Watcher.

It turned out that screenwriter Mesh Flinders, filmmaker Miles Beckett and former attorney Greg Goodfried, who took out the aforementioned trademark, had created the Lonelygirl15 ruse. Grant Steinfeld, a software engineer the team recruited to help distribute the videos, later told The New York Times he'd been required to sign an NDA. 

After the reveal, they released a statement:

We are amazed by the overwhelmingly positive response to our videos; it has exceeded our wildest expectations. With your help we believe we are witnessing the birth of a new art form.

Right now, the biggest mystery of Lonelygirl15 is “who is she?” We think this is an oversimplification. Lonelygirl15 is a reflection of everyone. She is no more real or fictitious than the portions of our personalities that we choose to show (or hide) when we interact with the people around us.

And with that, Lonelygirl15 became the first long con of the internet's attention economy -- the kind digital fame-seekers take for granted these days. 

After cutting ties with reality, Bree's storyline only got more bizarre leading up to the Lonelygirl15 finale in 2008. We were introduced to new characters and saw live action sequences. Bree's parents' religion turned out to be a secret society called the Order, and Bree and her new friends became fugitives to protect themselves before Bree herself was eventually killed off. 

In 2010 Beckett, the filmmaker, told SFGatethat the reveal in fall of 2006 didn't diminish the series' viewership. In fact, their highest numbers came in spring and summer of 2007. 

Beckett and Goodfried went on to create a production studio called LG15 Studios/Telegraph Ave and began monetizing the series with product placement for stuff like Neutrogena skincare. They eventually renamed the studio EQAL; they still run it today. Flinders left the series in 2007 to pursue his film career.

Rose parlayed her Lonelygirl15 notoriety into film and television roles, including a role in Lindsay Lohan's 2007 thriller, I Know Who Killed Me, that the world must never forget. She had a four-year stint on the TV dramedy Greek, and her most recent IMDB credit was a 2014 role on a TV series called Boozy Mom.

Rose has upwards of 4,000 followers on Twitter, where she recently commented on her iconic status as Lonelygirl15:

Tweet may have been deleted

The phenomenon of Lonelygirl15 couldn't happen in 2016 -- not quite the way it did a decade ago, anyway. Today any young person with a hint of fame-lust would create a social media trail hot enough to quickly evaporate any pretense of reality. 

The mystery is what made Lonelygirl15. Because there's nothing that the denizens of the Internet love more than having no idea what the hell is going on.

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