William F. Calvin was 38 and classified as an endangered missing dependent adult when he was last seen in Rocklin, California, on August 1, 1988. He is described as 6 feet 2 inches tall, about 155 pounds, with brown hair and blue eyes. At the time he was reported missing he had visible sores on his forearms and was noted to have health issues that made him dependent on others.

Investigators have kept the case open but report few details about the circumstances of his disappearance. Both dental and DNA records are available to help identify him if new evidence turns up. The Rocklin Police Department continues to seek any information that could explain what happened to William Calvin.

If anyone knew William, saw him around Rocklin in late July or August 1988, or has information that could help, please contact the Rocklin Police Department.