Moncer was last seen on February 18, 1982, leaving his residence in the 65000 block of Indian Run in Bellaire, Ohio. He has never been heard from again. Two days after his disappearance, his wife found his gray Dodge Aspen idling in a ditch at the entrance of Anco Mining Road. The car was mud-splattered, the keys were in the ignition, and the driver's side door was open. The interior of the vehicle was muddy and there were indications that a struggle had taken place. Shortly before he vanished, Moncer had gotten a note in his mailbox made of letters cut out of a magazine. It said, "Leave It Alone, Or You Are Dead." The person who sent the note has never been identified. There were reported sightings of Moncer in the area after his disappearance. His wife said she and their daughter were followed by a man in a truck for months, and for two years, a man would hide in the shadows outside their house. She believes the individual may have been Moncer himself. His case remains unsolved.