The mystery man in the rare photo of a young Princess Diana was revealed to be Adam Russell. The photo was taken during a skiing trip in 1980 -- before Diana became Princess of Wales. The pair had supposedly been injured during the skiing holiday and spent time together. A student at Oxford University, Russell supposedly liked Diana but they were just friends.

The photo has the words “not to be published”

written on it after the Daily Mirror decided not to make it public. The newspaper’s photographic archive was acquired by Caren Archive, which recently put the photo up for auction and is the reason we’re seeing the photo now. As for why it was never published in the first place ... well, that's a mystery to be solved another day.

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