Joshua got into an argument with his mother and departed from his Centralia, Illinois home on October 12, 1991. He climbed out his bedroom window and left with another boy. He has never been heard from again. According to one account, he was later sighted with another teenage boy, leaving a shopping center in a blue Ford Maverick with a friend, Terry Martin, and Martin's girlfriend. Martin and the other boy returned hours later. The car was mud-splattered and Joshua wasn't with him. He has never been heard from again. His mother reported him missing on November 12.

Martin is a suspect in Joshua's disappearance. A witness, Tonya L. Collins, who was in her teens in 1991, told authorities that she'd witnessed Joshua's torture and murder in a Satanic-type ritual in the Devil's Playground area of Centralia. She passed a polygraph about the case in 1996, but failed a second one in 2008. In 2008, she was placed under hypnosis and lead authorities to Joshua's supposed burial site in the Devil's Playground, but a dig of the area produced nothing. Collins named Martin as Joshua's killer. It was she who claims she saw them leave the shopping center together.

Martin has an extensive criminal record. In 1993, he beat a man with a baseball bat and almost killed him. In 1999, he was sentenced to 22 years in prison for the rape of a 6-year-old girl. He was paroled in 2010, but allegedly failed to register as a sex offender and was rearrested. That case is pending. Joshua and Martin burglarized a small grocery together. Joshua later testified against Martin in that case, and Martin was sentenced to four years in prison. Joshua was also allegedly seeing Martin's girlfriend in secret, something Martin denies. Martin admits that he was friends with Collins and Joshua in 1991, but says he didn't harm Joshua and doesn't know what happened to him. He stated Joshua often talked about running away, possibly to Kentucky, which was where his father lived.

Authorities believe Joshua is probably deceased, but they're unsure as to what happened to him. His case remains unsolved.