|On a dark, stormy night, Clay Thompson digs his way out of his grave. Was he buried alive? Um, no -- he died five years ago! But he's not decomposed or rotting, just dirty. He trots off and kills Benny, the man who killed him. So it begins.
Sam and Dean are dressed in suits, leaving messages for Bobby, whom they can't seem to reach though they are in his home town of Sioux Falls, SD. They interview a witness who saw Clay go into Benny's place and then come out, leaving Benny dead.
When the sheriff comes over, they introduce themselves as FBI Agents Dorfman and Niedermeyer. She calls to check it out and gets Bobby -- and recognizes his voice. The Winchester boys get their first glimpse into what others in ton think of Bobby -- that he's a misfit and a drunk!
They head to Bobby's and find him there -- and his house is clean. Something is up. He tells them there is nothing for them here and that they wasted a tank of gas. Nevertheless, they go check out Clay's grave and, naturally, it's empty. They go to his house and find him there, as if he hasn't been gone five years, with his wife and kid. But they confront him, and he seems to be quite aware that he has been dead and is now ... what? A zombie? Dean sure thinks so, and he tries to gank him, only to be stopped by the sheriff, who is very "zombie friendly" because her own deceased son has come back.
At the police station, Bobby admits, "There are zombies, and then there's zombies." He takes them back to his place and introduces them to his wife, Karen -- his dead wife. Even more interestingly, he tells them she was cremated. Yet, there she is, cooking and baking. Also, Karen has revealed to Bobby that she has no memories of her possession or the fact that Bobby killed her. The hunters talk about possible omens in the lightning storms that came through town, and they figure out that it's Death, the Pale Horseman. When the boys try to reason with Bobby that they'll have to do something about the zombies -- including Karen -- Bobby makes them leave ... not so politely.
Dean insists on watching Bobby's place to make sure nothing happens to him. Karen finds him and lures him into the house with -- what else? -- PIE! She reveals to Dean that she remembers everything: being possessed, Bobby killing her, the whole nine yards. But she won't tell Bobby that because she loves him and it would hurt him.
Meanwhile, Sam investigates in town, tracking out the others who have risen from their graves. An old zombie goes crazy and tries to kill him, which makes Sam realize that eventually they all will turn. Dean and Sam try once more to reason with Bobby, and this time he pulls a gun on them!
Dean heads back to Bobby's to sneak in and kill Karen, while Sam goes to alert the sheriff. However, Karen has realized she is turning and asks Bobby to kill her -- again. She also tells him that there was a skeletal figure when she rose who gave her a message for him. Though it's horribly painful for him, he finally does kill her, and just then Dean comes in. But that's not the end of it for them -- more zombies have come out to Bobby's place and are after them. They fight them off as long as they can but them run out of ammo.
Meanwhile, at the sheriff's house, her risen son is not feeling so well tells her he is very hungry. she sends her husband in with some soup, only to find that her husband has become her son's meal! Sam arrives, kills the zombie boy, and convinces the sheriff to round up the living people at the jail. They arm themselves and prepare to take out all the zombies. Again, the townspeople paint a bleary picture of Bobby as the town drunk.
In the nick of time, Sam and the sheriff arrive to rescue Bobby and Dean. At the graveyard, they burn all the bodies and make sure everyone is accounted for. Then Bobby tells them about the message that Karen relayed: Death picked his hometown because he was after Bobby. It was a vendetta for helping the Winchesters, as Bobby is one thing standing between Lucifer and his vessel -- Sam. Everyone looks grim, and Sam asks Bobby if he'll be all right. No answer.