Tulisa has shot straight to the top of the charts with her single Young.
The X Factor judge, who was named the world's sexiest woman by FHM magazine earlier this week, snatched the number one spot from Carly Rae Jepsen, whose single Call Me Maybe slipped to number two.
The song, written by N-Dubz bandmate Fazer, was not originally intended for her.
There was another new entry in the top five with Sparks by Cover Drive going straight in at number four.
We Are Young by Fun featuring Janelle Monae held on to the third spot, while Too Close by Alex Clare climbed from six to five.
Marina And The Diamonds went straight to the top in the album chart with Electra Heart going straight to number one, knocking Jack White's offering Blunderbuss down to number three.
Lana Del Rey continued to dominate the top five, with her album Born To Die up from number three to number two.
Norah Jones's newest offering Little Broken Hearts went straight in at number four, while Adele's 21, which this week overtook Michael Jackson's Thriller in British sales, took the fifth spot.
The other new entries were Marilyn Manson's Born Villain, in at number 14, and the Mystery Jets' Radlands at number 40.