In Biggles Buys a Watch, Mr McDew was a Scottish crofter who was the father of watch smuggler Roderick McDew. Mr McDew lived at his croft in Balburnie, near Forres, Scotland. Biggles met Mr McDew when he travelled to Scotland to follow a lead about an unidentified aircraft which had come in from the North Sea for three consecutive months always on the night of the full moon. Biggles believed the aircraft might be linked to the smuggling of watches which roderick McDew had been selling in London. Mr McDew told Biggles that Roderick visited him every month and always took long walks on the heather in the direction of a placed called "Dubn Chtais", thus giving Biggles a lead on the likely landing spot of the smuggling aircraft.