All is not well with the crooning kids of New Directions. "Glee: The 3D Concert Movie" sunk at the multiplex this weekend, roping in just $5.7 million and landing in 11th place at the box office.

So what happened? The film starred show faves Lea Michele, Cory Monteith and Chris Colfer, notched an A-plus CinemaScore from moviegoers under 25, and was coming off a "Glee" season that averaged more than 10 million viewers. MTV News consulted with a few industry insiders about the movie's opening and came up with five reasons to explain the box-office blunder:

The Demo
Successful 3-D concert films from Hannah Montana and Justin Bieber had one thing in common: a tween-centric audience. But as Jeff Bock, box-office analyst for Exhibitor Relations, points out, that's simply not the case with "Glee." "True fans of the TV series aren't just teens," he said. "The majority of fans are adults, and they certainly aren't the demographic that will run out to see a concert film, especially one that is in 3-D. Besides, Gleeks most likely went to see the live performances that the film is based on."

Bock argues that, for "Glee," the more accurate comparison is not Bieber's "Never Say Never" but "U2 3D." That film, he said, is the only other 3-D concert doc not geared toward a younger audience. "Despite U2 being one of the most popular bands on earth, that film barely scratched $10 million," he added.

The Marketing
"Glee" not only suffered from having a core audience unfriendly to 3-D concert docs, but its marketing campaign failed to attract new eyeballs. According to Brandon Gray of Box Office Mojo, "In its marketing, 'Glee' was strictly for the hard-core Gleeks, as it came off as redundant and self-congratulatory to more casual watchers who can see the television series for free. Despite the show's hype, only around an estimated 500,000 tickets were sold for the movie."

Even Fox TV execs reportedly weren't pleased with the marketing effort, with an unnamed source from that department telling Deadline, "I think it was a sh---y campaign that did not effectively communicate what the movie was or that the people who had seen it reviewed it positively. I think the feature company took a very laid-back approach, feeling their only job was to alert the core fans, and that's not enough to fill seats."

"The Help"
Even if the marketing campaign had been stronger, "Glee" still had to battle at the box office with "The Help," Emma Stone's segregation-era drama (which opened with $25.5 million). The concert film came out on the losing end. "It's quite obvious that 'The Help' came along and scooped up the attention of a huge section of female moviegoers," said Phil Contrino, editor of Boxoffice.com. "When you have a film that over-performs like 'The Help,' it causes a ripple effect, and 'Glee' felt the brunt of it."

The 3-D
So there were problems with demographics, marketing and a crowded multiplex. But let's not forget the public has become less receptive to 3-D in general, often choosing to go the cheaper 2-D route if the movie at hand doesn't feel like a must-see-in-3-D event. As successful as "Harry Potter and the Deathly Hallows, Part 2" was, for example, a majority of audiences still opted for 2-D screenings over opening weekend. For "Glee," the public had no such option. "Overall excitement was not too high, and the lack of a regular-priced 2-D option prompted cash-strapped teens to skip the film," wrote Gitesh Pandya of Box Office Guru.

The Overexposure
Finally, "Glee" found itself not only fighting external competition, but itself. Perhaps there's just a little too much "Glee" going on at the moment. "Kids can watch the real 'Glee' for free on Fox and faux 'The Glee Project' on Oxygen, so why spend their milk money on a movie ticket?" wrote Nikki Finke at Deadline. "And maybe 'Glee' is just over-exposed right now and not as cool as it was initially."

Check out everything we've got on "Glee: The 3D Concert Movie."

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