He has had several different actors portray him, including John Franklin in the movie series and Preston Bailey in the made-for-TV remake. Franklin's portrayal is the most popular because of his GHD. GHD is a disease that is the reason for his short stature, high voice, and young appearance. When he played the twelve year-old Isaac, he was actually 23, but nobody noticed it because his GHD made him look like a child.
Isaac Chroner was a boy preacher who came to Gatlin. According to the script, when he was twelve years old he led the children of the town in a massacre of all the adults and then resumed a place as leader of the remaining orphans. Eventually the children completely converted to his way of thinking and murdered their own parents at his will. It was around this time that he made the prophecy that He Who Walks Behind the Rows will awaken, when the daughter of the original chosen and the son of the original chosen provide a new generation of the chosen children. He orders that any child over the age of nineteen be killed and forbids leisure or playing games. However by the end of Children of the Corn, Isaac becomes powerful and is struck down by his own god.
After the events of the first film, the children of Gatlin manage to bring him into hiding, while preserving his status in critical care. When diagnosed it was found that he had suffered two fractures to the head which required stitching that his ankles and wrists were severely bruised his arm joints were torn, and he'd shifted two plates in his back He fell into a coma and woke up nineteen years later. He was determined to resurrect the forgotten religion, but couldn't successfully pull off all that was required of him, being weak and unwilling to meet the harsher demands of He Who Walks Behind The Rows.