When a powerful developer named Mr. Scheck wants to knock down all the stores and houses in Arnold’s neighborhood to build a huge “mall-plex”, it looks likes the neighborhood is doomed to disappear. But with the help of a superhero and a mysterious deep-voiced stranger, Arnold and Gerald will need to recover a crucial document in order to save their beloved neighborhood.

An upcoming two-hour American animated television film split into two parts. Based on Craig Bartlett’s Hey Arnold! TV series, it will serve as a sequel to the series finale in which Arnold found his father’s journal and read about the life of his scientist parents, including their first meeting, birthing him, and a map showing the route they took to the San Lorenzo before they disappeared.