The tables end up being turned on Philip this week when one of his own pictures are put under the microscope.

Fiona and Philip take a look at the history of three paintings bequeathed to the National Museum of Wales after their owner died in 1951. It was always thought that the paintings were by landscape artist JMW Turner, but only months after the museum took ownership, experts said that they were fakes.

Fiona and Philip examine a painting that owner Patrick Rice thinks is by Edgar Degas. If its genuine, it could be worth about £500,000. They trace the artwork back through time to find out whether it really was created by one of France's greatest artists.