I love it when stuff like this happens, albeit usually the film is exposed already. Best time it happened to me was when I got hold of my Mum's old Brownie (last used in the mid 50's) and found a partially exposed roll of Verichrome (I think). I got it developed and found some very degraded, almost ghostly snaps of my grandparents (both dead by then) that my mother had taken when she was a kid. Very strange experience for both of us.
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