Matt is in Northumberland where he discovers that Hadrian's Wall is a stronghold of one of the UK's rarest plants and he learns how a world-famous discovery at the wall just 50 years ago has told people most of what they know about Roman armour.
A seasonal edition of the show exploring how Autumn marks a tide of change for the countryside. Matt looks at how conkers are at risk from tiny predators. Ellie goes foraging in the forests with Raymond Blanc. John Hammond looks at the science of the season with Tom Heap. Adam looks at how turkey's are prepared. Richard looks at the arrival of grey seal pups.