Springfield is experiencing an unusually strong thunderstorm, and the rain is causing roofs to leak all over town. Homer devises a unique solution for getting the rain water out of their house that ultimately fails and sends him dejected off to Moe's, where he ruins Lenny's surprise party. Homer goes off wandering and finds himself at a bar called Knockers, where he makes a new friend named Ray, who is a licensed and bonded roofer.
Marge takes the kids on some errands while Homer and Ray almost begin the roof repairs; they screw around and never get around to doing any work until he gets called away. Marge wants Homer to fix the roof by himself.
Homer runs into Ray at the Builder's Barn and Ray promises to stop by later and help him with the roof. Homer waits for him, but Marge is skeptical that Ray even exists when Ray never shows up. Marge has Homer placed in the mental ward of the hospital and she and no one else can confirm that Ray really exists. Dr. Hibbert recommends and gives Homer electro-shock therapy.
Six weeks later Homer's treatments are over and to everyone's surprise Ray turns up at the hospital to celebrate Homer's release. Plausible explanations, even one by Stephen Hawking, are given to explain why no one had ever seen Ray before.