 Gollum deliberately leads Frodo Baggins there in hopes of recovering the One Ring when Shelob attacks Frodo.The plan is foiled when Samwise Gamgee greatly injures Shelob with Frodo's Elvish dagger, Sting, and the Phial of Galadriel.Shelob was an "evil thing in spider-form...[the] last child of Ungoliant to trouble the unhappy world", living high in the Ephel Dúath mountains on the borders of Mordor.