|Travis Weaver and Dustin Burwash are working on the construction at a new housing complex when Dustin suddenly falls into a sinkhole that opens beneath him. By the time Travis gets back to him with a rope, Dustin is dead.The local newspaper reports that Dustin died from the human form of Mad Cow Disease, but Sam is suspicious. They head out to Oklahoma gas and Power to talk to Travis but end up none the wiser about the way Dustin died. Their next plan is to visit Oasis Plains - the housing complex Travis and Dustin were working on.
Sam climbs down the sinkhole but finds nothing more than a dead beetle. He suggests to Dean that maybe Dustin was eaten by the bugs, but Dean isn't sure about itl. They notice signs for a barbeque get together for anyone interested in purchasing one of the new Oasis Plains homes and decide to head over. They start asking a few questions, but still find nothing of any importance. They do, however, meet Matt Pike, the son of the developer, who seems to have a distinct interest in bugs. They wonder if maybe he has something to do with the bugs that killed Dustin.
That night, Linda Bloome, the realtor for Oasis Plains, is attacked by hundreds of spiders and falls into the glass shower screen, killing herself. Sam and Dean sneak into her house to investigate and find several dead spiders on the floor. They talk further to Matt who reveals that he has noticed some strange behaviour from the local insects recently - as though they are congregating in the area.
Digging around, Dean uncovers an old skull which they take to a local college professor to look at. With the help of him and a local Native American Indian called Joe White Tree, they soon discover that Oasis Plains is being built on a cursed site. By the end of that night, everyone white person living in the area would be dead.
They rush to try and get the Pike family out of their house, but aren't quite fast enough. They find themselves trapped inisde the house along with the Pike's just as the bugs start attacking. With the help of a can of bug spray and a lighter, they manage to fend off the insects until the sun rises and the curse is ended.