A "previously unseen" nude photograph of Marilyn Monroe has been exposed as a fake - the image is that of pop superstar Madonna. Movie fan Lawrence Nicastro invited reporters to Las Vegas for the unveiling of the poster-size picture of who he believed to be screen siren Monroe posing as a hitch-hiker. But Nicastro was shocked when a journalist pointed out the celebrity in the photo was none other than the Like A Virgin hitmaker - an image taken from Madonna's controversial 1992 book Sex. And the 73-year-old was particularly surprised at the revelation because he had called on Monroe expert Chris Harris, who assured him the grainy photo of a naked blonde girl smoking was genuine.