"Is it true all British people can trace their ancestry to Vikings and how do ancestry DNA tests work?" asks Chloe Mann from Worthing.
Genetic ancestry tests promise to reveal your ancestral origins and map your global heritage, but do they? Rutherford and Fry are here to bust some myths.
Adam takes a trip through Norse history with Viking historian Janina Ramirez, whilst flying over the Medieval town of Ludwig.
Meanwhile Hannah discovers how DNA ancestry tests work with evolutionary geneticist Mark Thomas, including why most of us can rightly reclaim our royal lineage.
If you have any more Curious Cases for the team to solve, please send them in for consideration: curiouscases@bbc.co.uk
Presenters: Adam Rutherford, Hannah Fry Producer: Michelle Martin
First broadcast on BBC Radio 4 in November 2018.