A couple of years ago, local man Derek Batten was driving through the village of Alderton, near Northampton, when he was surprised to see a sign advertising a castle and moat for sale. He was intrigued because he didn't even know there was a castle in the area. He decided to find out more – and ended up buying what was believed to be the remains of a Norman castle, now almost completely covered by trees and vegetation. Unable to discover very much else about the site, he contacted Time Team. The Team's task was to find out who built it, when, and how much of it remains.