Plot
Farmer Vincent Smith and his younger sister, Ida, live on a farm with an attached motel, named "Motel Hello". Vincent's renowned smoked meat is actually human flesh. He sets traps on nearby roads to catch victims. He buries the victims up to their necks in his "secret garden", then cuts their vocal cords to prevent them from screaming. They are kept in the ground and fed until they are ready for "harvest". Ida helps Vincent, as they both see the victims as animals.
Vincent shoots out the front tire of a couple's motorcycle. The man, Bo, is placed in the garden, but Vincent brings the woman, Terry, to the motel. Sheriff Bruce, Vincent's naive younger brother, arrives the next morning. Vincent tells Terry her boyfriend died in the accident and was buried. A trip to the graveyard shows his crude grave marker. With nowhere to go, Terry decides to stay at the motel. She gradually becomes attracted to Vincent's honest manner and folksy charm, much to the dismay of Bruce, who tries to woo her without success.
Vincent captures more victims by placing wooden cardboards of cows in the middle of the highway to cause his victims to stop, allowing him to capture them. With this method, he manages to capture Suzi and uses sleeping gas to put her to sleep. He also places a fake ad and lures in a pair of swingers, who believe the hotel to be a swing joint. The next day, Vincent suggests that he teach Terry to smoke meat. Ida becomes jealous and attempts to drown Terry, but Vincent arrives to save her. This causes Terry to fall completely in love with him, and she tries to seduce Vincent. Vincent denies her advances, saying they must marry first. She agrees to marry the following day.
Bruce visits the motel to protest Terry's choice. He tells Terry that Vincent has "syphilis of the brain". Vincent arrives and drives off his brother with a shotgun. Vincent, Terry, and Ida drink champagne, but Ida drugs Terry's glass, and she faints. Ida and Vincent then prepare some victims for the wedding. Meanwhile, Bruce investigates the disappearances and becomes suspicious of his brother.
Vincent and Ida kill three victims and take them to the slaughterhouse. As they remove the victims' bodies, the dirt around Bo loosens, and he begins to escape. Bruce sneaks back to the motel to rescue Terry, but Ida returns. She ambushes Bruce and knocks him out, then holds Terry at gunpoint, to the meat processing plant, where Vincent reveals his secret. Terry is horrified by the prospect of smoking human flesh. Meanwhile, Bo escapes and frees the other victims from the garden. Ida goes back to the motel to get something to eat, but the victims attack her and knock her unconscious. Terry tries to escape, but Vincent gases her and ties her to a conveyor belt. He is interrupted by Bo, who crashes through a window, but Vincent strangles the weakened Bo.
Bruce awakens and finds one of his brother's shotguns. He goes to the plant but finds that his brother has armed himself with a giant chainsaw and placed a pig's head over his own as a gruesome mask. Vincent disarms his brother, but Bruce grabs his own chainsaw and duels with Vincent. During the fight, the belt restraining Terry is activated, sending her slowly toward a cutting blade. Despite his wounds, Bruce drives the chainsaw deep into Vincent's side. Bruce frees Terry and returns to Vincent. He gasps out his final words, leaving the farm and the "secret garden" to Bruce, and lamenting his own hypocrisy in using preservatives.
Bruce and Terry go to the "secret garden" and find only Ida, who is buried headfirst. As they leave the motel, Bruce comments that he is glad he left home when he was 11. Terry suggests burning the motel, claiming it is evil.
Afterward, the neon sign reading "Motel Hello" short-circuits and permanently darkens the "O".
