Nightwights are a strain of Scriven who went to live underground after the Sixty Minute War They were mentioned briefly in Fever Crumb. When Fever was traveling through the tunnels towards London, she thinks of the mysterious nightwights, though she doubts their existence. Later on, in Scrivener's Moon, she met them. They seemed barbaric at first as they made human sacrifices etc., but later when Fever met them they seemed much more human.