Dr. Otto and the Riddle of the Gloom Beam is a 1985 American science fiction comedy film starring Jim Varney. It was written and directed by John Cherry. It is the first film to feature the Ernest P. Worrell character, but it has a slightly darker tone than his later films. It was shot in Fall Creek Falls State Park, Boxwell Scout Reservation, and Nashville, Tennessee.
https://archive.org/details/dr.-otto-and-the-legend-of-the-gloom-beam-with-intro
they did. If I remember correctly he started doing some commercials for a roofing company, then a natural gas company, and finally the character was so popular he went to Hollywood.