Motel Hell is often more of a black comedy than a horror film. Farmer Vincent and his sister Ida run both a motel and a successful smoked meats company. This being a horror film involving a chainsaw, the jerky they sell has human flesh in it, which they obtain by causing accidents on a nearby road. Instead of killing their captured prey right off, the farmers literally plant them in their garden, burying them up to their necks. They then slice their vocal cords and force-feed them pig slop to fatten then up for butchering. It's about as silly as it sounds, with their planted victims making a zombie-like growling sound all of the time and Farmer Vincent using swirling lights to trip them out so they're calm for slaughtering time.
All of that's not even much of the movie, which is mostly about crash victim Terry. Vincent decides to spare her and invites her into his home to stay. None too bright, she buys his explanation that he has already buried her traveling companion because he died in the accident. She grows to love Vincent and is eager to help with the meat business. Sister Ida grows jealous. Terry eventually discovers the horrible secret of the meat. The dashing sheriff rescues her. It's nothing much special, except for the fantastic chainsaw duel at the end.