Short answers, pulled from the story.
James Dallas Egbert III was a sixteen-year-old child prodigy with an IQ of 160 who walked into the steam tunnels beneath Michigan State University in January 1979. He had been accepted into the university's engineering program and was among the youngest students in the institution's history. He disappeared from the public eye after entering the tunnels and was never seen again.
William Dear was a private investigator with a background in psychology hired by James's parents to find their son. He proposed the theory that James had entered the tunnels to play a live-action version of Dungeons and Dragons using the steam tunnels as a real-world dungeon. This theory became the central focus of the investigation and the subsequent book that bears his name.
James Dallas Egbert III disappeared in January 1979 when he walked into the steam tunnels beneath Michigan State University. He was sixteen years old at the time and had written a letter to his parents explaining that he was entering the tunnels to commit suicide. He was never seen by the public again after this event.
The media focused on Dungeons and Dragons because James was a dedicated player of the new tabletop role-playing game. They seized upon the idea that he might have entered the tunnels to play a live-action version of the game, which ignited a moral panic across the United States. This narrative led to the banning of the game in some schools and portrayed the game as a dangerous influence on vulnerable teenagers.
The novel Mazes and Monsters was written by R. A. Salvatore and became a bestseller that was adapted into a television movie. It depicted a similar scenario and was blamed for inspiring the disappearance of James Dallas Egbert III. The media used the book to cement the link between the game and the tragedy, overshadowing the real issues facing James.