The final three contestants return home to the UK and go head-to-head to find the treasure. To help, they've been allowed to ask the eliminated contestants for advice and support.
The key to finding the treasure is the 400-year-old battle between Elizabeth I and Mary Queen of Scots for the English and Scottish thrones.
The first to arrive gets to choose. Get it right and they win £50,000 in gold, lose and they walk home with nothing.
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