Missing person was last seen on Mark Twain Lake, Ralls County, MO, in a bass boat that was involved in a single boat accident. Mr. Plummer was a passenger in the boat and was thrown overboard. The boat driver was unable to locate Mr. Plummer. An extensive search of the area by Law Enforcement was conducted and his body was not found. It is believed that Mr. Plummer drowned although his body has not been recovered.