The boyband's fans are known to be a little bit wild and it was about time one of the fans got the lucky view.
Whilst the boys Liam, Louis Tomlinson, Niall Horan, Harry Styles and Zayn Malik continue their US tour, this one fan has the boys a little shaken up.
When taking a break from performing the boy’s bodyguards were distracted when a ray of fans attempted to take over the boys changing rooms.
However one sneaky fan won her opportunity will they were distracted.
A source said: "Liam was stunned when he saw her in the changing room he couldn’t believe she’d got past security.”
"For one thing, he was in the middle of getting dressed and had no idea what she was going to do, as their fans in the US are mad."
But putting their embarrassing changing room scenario behind them, the boys are enjoying their tour.
Last night the boys were performing in Fairfax, Virginia, and took to Twitter to thank there US fans.
Niall firstly tweeted his appreciation by writing: "Incredible gig in fairfax tonight! Sooooo loud ! On another level! We had soo much fun on stage!," and Harry then added: "The show tonight was absolutely insane! Thank you for having us Fairfax .xx."
Well, next time boys try locking the door…. Liam's not the only person to have been caught out naked as Zayn Malik's cleaner once caught him in the nude!