The team delves deeper into the secrets of the skilled communities who built medieval castles. The stonemasons working on the castle walls are dependent upon blacksmiths, whose metalwork was magical to the medieval mindset, and upon carpenters employing sophisticated geometry. Ruth Goodman, Peter Ginn and Tom Pinfold discover the ways in which every aspect of construction at Guédelon Castle requires the masons, blacksmiths and carpenters to coordinate their efforts - from making and sharpening tools, to processing wood and securing timber scaffolding on the castle walls.