In December 2005, a dog walker discovered the body of a Swedish woman on Prestwick Beach in Ayrshire on Scotland's west coast.
Annie Börjesson's family were told the 30-year-old had died by suicide - but something felt wrong.
Keep following StoryCast to find out #WhatHappenedToAnnie. Episode two of six will be released on 5 December.
Narrated by Rona Dougall.
Produced by Robert Mulhern.
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