Gríma Wormtongue is a character from J.R.R. Tolkien's The Lord of the Rings. He serves as an advisor to King Théoden of Rohan, but he is actually a spy for the dark lord Saruman. Gríma uses deceit and manipulation to weaken Théoden and influence his decisions, leading to the king's decline. Wormtongue is characterized by his sly demeanor and persuasive speech. He often speaks in a soft, whispering voice, which reflects his treacherous nature. Ultimately, he is exposed and rejected by the people of Rohan, illustrating the theme of corruption and the struggle against evil in Tolkien's work.