The black-and-white photo shows a teenage Diana on a Swiss ski holiday lounging on the lap of a young man, who has been identified as Adam Russell, the great-grandson of former prime minister Stanley Baldwin. He is reading a book and resting it on Diana's shoulder.
A bottle of liquor rests on a window ledge above her head, creating an image that was certain to be unfit for a future princess, and is one that was marked "not to be published," according to Britain's Daily Mirror, which purchased the picture in Feb. 26, 1981 – just two days after the then-Diana Spencer was engaged to Prince Charles.
The photo was kept hidden in the paper's archives until it was purchased seven years ago by the private Caren Archive. It is now set for auction by RR Auctions in New Hampshire, and is being described as a "salacious teenage image of the future princess."