Gríma Wormtongue (unknown — Nov 3, 3019), son of Gálmód, one of the secondary characters in the Lord of the Rings book (and movie). By all save Théoden King he was called the Wormtongue. Gríma claimed to be friend and counselor of the king, but actually he was a spy and servant of the wizard Saruman for a very long time, weakening the kingdom of Rohan to assist Saruman in defeating it.
A "witless worm" he was once called by Gandalf, and a worm he was, but not witless. In fact Gríma was bold, cunning and knowledgeable. But he was also mean, sniveling and devious. Among his less worthy doings in Edoras was stealing various valuable items and keeping them in his chest. The most notable possession was Herugrim, Théoden's sword (Gríma denied this accusation). After arrival of Gandalf and exposure of Gríma's evil deeds, he decided to openly join Saruman, ignorant about the impending destruction of Isengard by Ents.
Later, after Gandalf confronted Saruman in Orthanc and broke his staff, Gríma threw the Palantír from one of the upper windows, aiming to hit Saruman (who was standing on the lower balcony) on the head, but missing. He later traveled with Saruman to the Shire, where Gríma killed several hobbits (we know about Lotho Sackville-Baggins) and probably ate some of them (again, Gríma denied this accusation, claiming that Saruman forced him to do it). Finally, when Saruman was driven away from the Shire by rebel hobbits, Wormtongue finally succeeded in killing his master, by cutting his throat. Gríma was then promptly killed by hobbit archers.
In the movies The Two Towers and The Return of the King, Gríma is played by Brad Dourif. His character is slightly different from Tolkien's Gríma. For example, he tries onscreen to "seduce" Éowyn, using Gandalf's lines from the original book. He also sheds a tear when he sees Saruman's army of Uruk-Hai, making thousands of fans wonder, what was exactly the reason why he shed this tear if he was working against Rohan from the start. Due to the "Scouring of the Shire" portion of ROTK being expunged from the movie version of the story, Gríma's only scene is one that was deleted from the theatrical release, in which he appears with Saruman at Isengard when Gandalf et al tries to convince Saruman to reform and help them. There, Gríma stabs Saruman in the back, killing him, after which he himself is killed by Legolas' arrow. This scene is included in the Extended Edition.