Adkins was last seen out on the Gulf of Mexico, sixteen miles west of Tarpon Springs, Florida, on July 19, 1987. He was scuba diving with a friend. Both of them surfaced and began swimming to their boat. Adkins's friend made it safely to the boat, but Adkins vanished and has never been heard from again. The United States Coast Guard searched for him and located his oxygen tank and wetsuit. He is believed to have died in a mishap at sea.