Is it a cut, is it a wig, is it a pin job...? We just can't work out the mystery of Heidi Klum's magical disappearing hair! Spotted at the launch of the new New York Victoria Secret store, Heidi had her trademark super-sleek long locks. Fast forward a few hours to the cocktail reception and Heidi re-appears with a shoulder-length bob (the ‘lob'). Did Ms Klum pop into a salon between jobs - or is it a genius example of hair pinning. And the biggest question of all - why..? Answers on a postcard please.