S1·E9 Time Town

Dorothy and the gang are searching for the Wizard when a pidgeon flies down and has a singing telegram for Dorothy - The Wizard of Oz is in the Emerald City! They Travel to the Emerald City and find it in ruins. the Wizard has lost his memory, is now a farmer, and dosn't even know who Dorothy is! Glinda arrives and tells Dorothy that The Wicked Witch has stolen the book that records everything that has ever happened in Oz, ""the History of Oz"". She must be stopped before it's completely erased and rewrites for her own. Glinda tells them that the book was last seen in Time Town. As she's telling them, her page is erased. She turns into an old lady and says that her name is not Glinda. The 4 of them travel to Time Town. and with the farmer Wizard, and the guardians of Time Town, they go to Pendulam Mountain. The Lion breaks the spell and now everything is back to normal in Oz!