In 1985, Tilquhillie Castle, in the picturesque Royal Deeside region in Aberdeenshire, was a ruinous Z-plan Scottish tower house. Originally built in the middle of the sixteenth century for the important local Douglas family, it had been derelict for nearly forty years, inhabited only by bats. John Coyne and his wife Kay had the vision and dedication to buy this property and restore it to its former glory, working together with talented local craftsmen over many years. The philosophy that guided the restoration was based on authenticity, informed by the building itself. During the process, a picture emerged of a building that was the product of an unknown but highly gifted master mason, probably a Frenchman. Details of his genius were evident everywhere in the building. He had designed and built a simple and elegant fortified dwelling for the Douglas laird, which stood in defiance of any potential foe and provided evidence of the social, political and historical norms of a bygone era. Although of modest proportions as castles go, Tilquhillie Castle is revealed as an architectural masterpiece of the period.