Simon Cowell's house was covered in toilet paper by Fifth Harmony.
The media mogul who turned 54 today was given a birthday treat by the girlband - which includes Ally Brooke, Camila Cabello, Dinah Jane Hansen, Lauren Jauregui and Normani Kordei - who rose to fame on X Factor USA last year.
According to gossip website TMZ.com the five-piece girl group made a mess around his home in Beverly Hills, Los Angeles, before leaving him with a banner which poked fun at his age, and read: "Happy 87th Birthday Simon! Love, Fifth Harmony."
Singer Demi Lovato - who is on the X Factor USA panel alongside the Simon, Paulina Rubio and Kelly Rowland - was amused by the prank and tweeted: "HAHAHA YES @FIFTHHARMONY (sic)"
The Heart Attack hitmaker will be accompanied by the girls on her Neon Lights tour and is looking forward to getting up to some more mischief with them.
