Gollum
Gollum is a fictional character from J. R. R. Tolkien's legendarium. He was introduced in the 1937 fantasy novel "The Hobbit", and became an important character in its sequel, "The Lord of the Rings". Gollum was a Stoor Hobbit of the River-folk, who lived near the Gladden Fields. Originally known as Sméagol, he was corrupted by the One Ring and later named Gollum after his habit of making "a horrible swallowing noise in his throat".
Gollum
In Jackson's films, Gollum has a split personality: the childlike "Sméagol" and the evil "Gollum". Screenwriters Fran Walsh and Philippa Boyens included scenes in "The Two Towers", "The Return of the King" and "" in which "Gollum" and "Sméagol" argue, with Serkis slightly altering his voice and body language to play the two as separate entities. His dual personality was also emphasized by different pupil dilation – "Gollum" has small, piercing pupils and "Sméagol" larger, noticeably dilated pupils – and by positioning the two on different sides of the screen.