Prior to working on Lord of the Rings, Regelous had worked as a Technical Director on Jackson's earlier movie, The Frighteners. In 1996, Jackson asked Regelous to work on The Fellowship of the Ring, the first movie in the LOTR trilogy.[2] Regelous was asked by Jackson to come up with a program that could create the huge battle scenes in the trilogy. Regelous wrote the software over several years and it was used in all three Lord of the Rings movies.[3]
The 'revolutionary' new software generated individual 'agents' which, at the time, were the closest any program had come to artificial intelligence in digital characters.[4]