Katy Perry: 'Last Friday Night (T.G.I.F)'

"There's a stranger in my bed/ There's a pounding in my head/ Glitter all over the room," Katy Perry announces on the opening of her latest chart botherer. While we'd happily accept such behaviour from her (pre-Brand, natch), spare a thought for her doppleganger Kathy Beth Terry, who, judging from her pigtails, taped-together specs and denim all-in-one in the accompanying music video, is a first time offender when it comes to throwing a house party. Don't worry love, we've all been there.

"Barbie's on the barbecue/ This a hickey or a bruise?" she ponders over light 'n' perky guitar-jam riff courtesy of Messrs. Luke and Martin, before retelling a night of debauchery that includes streaking, skinny-dipping and ménage à trois-ing with the hottest jocks on the block - and in true sorority blowout style, vows to do it all again next week. The result is the candy corn of pop tunes; light, sugary and worryingly addictive - in other words, the perfect mix for her fifth consecutive US chart-topper .

Watch Katy Perry's 'Last Friday Night' music video below: