"El Viaje Misterioso de Nuestro Jomer (The Mysterious Voyage of Homer)" (a.k.a. "The Mysterious Voyage of Our Homer") is the ninth episode of Season 8. A more accurate translation of the episode title from Spanish is "The Mysterious Trip of Our 'Jomer'." Nuestro is Spanish for "our," and "Jomer" is a Spanish pronunciation wordplay on "Homer" (in Spanish, the letter J is pronounced as an English H).
After Homer downs several Guatemalan insanity peppers at the annual chili cook off, his consciousness goes on a mystical journey, complete with a talking coyote spirit guide, to discover his soul mate.
It's time for the annual Springfield Chili Cook-Off, and Marge tries everything to keep Homer from finding out about it, including cutting the ad out of the newspaper, disconnecting a phone call between Homer and Lenny, and even smoking a cigarette to cover up the smell of the cook off wafting over the city. Homer is surprised by her smoking and opens the front door for some fresh air, then realizes the cook off is happening when he smells the spices from the house. He begs Marge to go, but she at first says no, reminding Homer of his drunken behavior at last year's Cook-Off. However, Marge changes her mind and makes him promise not to drink any beer, and the family quickly races to the Cook-Off.
After they arrive, Homer is revealed to be a revered chili critic whose opinion is highly important to all the cooks. He demonstrates an extraordinary ability to withstand hot foods, until he falls victim to Chief Wiggum's chili spiked with "The Merciless Peppers of Quetzlzacatenango," humiliating himself in front of the whole town. Feeling the effects of the extremely hot peppers, Homer races desperately around in search for anything to drink, grabs a tray full of beers, and nearly drinks them when Marge catches him. Homer doesn't actually drink the beers (instead simply dousing his tongue with them), but Marge is still furious and storms off. Homer resorts to drinking water and discovers that candle wax can protect his mouth from the pepper's spiciness. Homer then returns to Chief Wiggum's stand and amazes the whole town by eating several peppers in quick succession. However, while his mouth remains unaffected, his stomach is not as lucky as the peppers raise all hell on his digestive track to the point of hallucinations, causing him to run off in fear.
In his hallucination, Homer ends up in a desert, a bizarre world where the laws of physics don't apply, wherein he breaks the sun and encounters strange creatures such as a puddle that transforms into a snake. Homer is then instructed to follow a tortoise and climb a pyramid which grows to an enormous height, where he meets his spirit guide, a coyote voiced by Johnny Cash. The coyote advises Homer to find his soulmate, and questions Homer's assumption that he has already found her in Marge. Then the coyote jumps down from the pyramid and runs off. Homer calls for him to come back, but then he turns to see a ghost train barreling straight towards him.
Just when the train is about to run over him, Homer regains his senses and rationalizes his dream. For example, he compares the desert he wandered in to the real-life location where he woke up (a golf course's sand trap) and the pyramid to the course's pro shop, and the talking coyote to a talking dog. After returning home, he finds Marge (still believing that Homer got drunk, thus breaking his promise) angry with him for his odd behavior at the cook-off. Feeling that Marge doesn't understand him at all, and remembering the coyote's words, Homer sets off on his own quest to find his soulmate. After looking among the patrons in Moe's Tavern and responding to a Personals ad placed by "GBM," Homer happens to see the lighthouse and concludes that the lighthouse operator must be the loneliest guy in town.
Homer goes to the lighthouse and is elated to see a sign reading "This lighthouse operated by Earl." Shouting "No more loneliness for Homer and Earl," Homer goes inside to meet his new friend. He is frustrated, however, to discover that the lighthouse is operated by a machine: E.A.R.L., short for Electronic Automatic Robotic Lighthouse. Homer destroys the lighthouse's giant bulb in a bout of recklessness, but Marge arrives and they fix it, warning a ship that's just about to run aground. They decide they really are soulmates, and Homer mocks what he calls the "space coyote". Unfortunately, the ship runs aground anyway, spilling its precious cargo of hot pants. The townspeople then turn up and help themselves to free hot pants and the episode finishes with everyone singing the song "Who Wears Short Shorts?"