An early screening for One Direction's '1D: This Is Us' 3D film at the Grove in Los Angeles almost ended in disaster when overeager Directioners stormed the theater.

The event was a first come, first serve showing of the Morgan Spurlock-helmed flick, slated to begin at 10AM for the first 100 Directioners on line. When the first 100 in line, who confessed they'd gotten to the theater at 3:45AM, got in and the rest were turned away, it got crazy.

About 15 minutes after the 100 Directioners were seated in the auditorium, there were still empty seats -- and still angry fans outside who wanted in. An usher told the audience to stay calm and remain seated, but warned that other fans were trying to bumrush the theater -- yikes! He added that cops were on the way and requested other employees to help him deal with the angry teens, tweens and moms.

"They charged and went straight past the ticket takers for the doors of the actual theater screaming, 'Let us in! Let us in!'" a witness told The Los Angeles Times. "It took about a half an hour before a police car came with two policemen in it. They started palming kids down and shoving them outside."

One member of the mob (no, not that mob!) confessed, "When I got inside, the red ropes that block the entrance to the theater were on the floor. It was pretty scary because people were tripping on the floor and pushing and stuff like that."

Still, a source told E! News that it may not have been that big of a deal after all. "It was invite-only with a first-come first serve basis. People that weren't able to get in were stuck outside the theater," the source explained. "Someone shouted that the band was actually there and that's when a bunch of screaming girls ran in and tried to get inside." However, the source continued, "Security was able to stop anyone from entering. It was a non-incident. The screening carried on as planned."

Geez. Being a Directioner isn't easy! Here's hoping there aren't any more scary incidents at further screenings of One Direction's movie debut, which hits screens Aug. 30.