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The Architect has come down with a case of the sneezing fits. He tells Cotterpin Doozer to take over at the Doozer Design Office until he can return (which is normally four and a half days from the start of the fits). In his absence, Cotterpin designs the Perfect Doozer Building. It's so perfect that even the Fraggles aren't allowed to eat it - it will exist forever! When the work is done, all the Doozers agree that it's no use getting back to making regular old buildings. Instead, they can spend their time relaxing. But after a while, the Doozers are getting bored...

The book includes several new Doozer characters, including Socketwrench Doozer, Jigsaw Doozer, Sandpaper Doozer, Drillbit Doozer, Ratchet Doozer and Crankshaft Doozer.