One Direction are at the top of their game these days. After rising to the top of the charts earlier this year with their debut album, Up All Night, the boy banders have continued to reign over the hearts of Americans, thanks to their infectious pop tunes.

Just last week, they took home three Moonmen at the VMAs (Best Pop Video, Best New Artist and Most Share-Worthy Video for their "What Makes You Beautiful" clip) and stormed the stage at the famed Staples Center, much to the delight of the ladies in the room. So, could Simon Cowell, their manager who discovered them on U.K.'s "X Factor" in 2010, ever have imagined they'd get this big?

"No! I mean, you know, I thought they would work as a band, but you can't predict these kinds of things," he told MTV News at the premiere of the second season of the Fox version of the show, which kicked off this week.

"But it's down to them," he continued, crediting the guys for putting in the effort to be successful. "They've worked hard. They work really well as a group. The records are good. They're nice guys to work with. So the world, right now, is theirs."

While it's been two years since the fellas competed on the show, their presence was felt on Wednesday night's premiere. Not only did they pre-tape a message that ran at the top of the show where they welcomed Demi Lovato and Britney Spears to the "X" family, but Cowell also addressed rumors that co-judge Demi might be dating 1D member, Niall Horan. His love advice for her when it comes to the fair-haired singer? "Keep away from him. He's pure. OK?" he teased.

Well, whatever the case may be between Niall and Demi (she maintains they are just friends), the guys will continue to dominate this fall in the music world. They drop their single, "Live While We're Young," on October 1 and then their sophomore album release, Take Me Home, will hit stores on November 13.

How did you know One Direction were going to make it big? Let us know in the comments!