Hugh Dennis and the team take on their first prehistoric dig as they try to unearth ancient roundhouses in the village of Stretton in Staffordshire. Their mission is to work out just how far back in time the settlement dates - is it Bronze Age, Iron Age or from the early Romano British period? Nobody has ever excavated the site before, and for the first time the team dig up a school playing field.

The archaeologists uncover a 19th-century prison with a difference in Wiltshire. Devizes House of Corrections was one of the first panopticon style prisons built in the UK, with its all-seeing central guards' tower which allowed just a handful of guards to monitor and control the lives of hundreds of prisoners. The team want to uncover the prison's lost structures, reveal the secrets of what went on behind its walls and discover just how secure and inescapable it really was.

Hugh Dennis and the team are in Odiham, Hampshire, searching for the house of Sir Frances Walsingham, the head of Elizabeth I's Secret Service. It is the first time the site has ever been dug, so with very little to go on, our team want to locate the house, work out its size and scale, and what Walsingham may have used it for. As part of the investigation, Hugh turns his hand to spy craft as he learns how Walsingham used to break codes.