Fear Cay is an island location that appears in the Doc Savage adventure Fear Cay. It is the island that Dan Thunden is shipwrecked on and locates the medicinal herb Silphium, which becomes the driving force behind Fountain of Youth, Inc.. During his time there, Dan Thunden built numerous traps which he uses to deal with unwitting foes. There is also a terror on the island that turns a man into a skeleton in minutes. Located somewhere in the Caribbean.