Demogorgon is a monstrous creature from the popular Netflix series 'Stranger Things.' Serving as one of the main antagonists in the first season, the Demogorgon is a terrifying entity from the parallel dimension known as the Upside Down. It preys on humans and animals, causing fear and chaos in the town of Hawkins. Its appearance marks the beginning of the supernatural events that drive the series' plot and bring the main characters together.