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Finian's Rainbow is a musical with a book by E.Y. Harburg and Fred Saidy, lyrics by Harburg, and music by Burton Lane, produced by Lee Sabinson. The original 1947 Broadway production ran for 725 performances, while a film version was released in 1968 and several revivals have followed. Finian moves to the southern United States (the fictional state of Missitucky is a combination of Mississippi and Kentucky) from Ireland with his daughter Sharon, to bury a stolen pot of gold near Fort Knox, in the mistaken belief that it will grow. A leprechaun follows them, desperate to recover his treasure before the loss of it turns him permanently human.

The sharecroppers begin unpacking extravagant gifts to themselves from their new accounts. Sharon and Finian celebrate the end of class-distinction that comes with wealth ("When the Idle Poor Become the Idle Rich"). Shears and Robust show up wondering when the gold will be discovered that will pay for the credit. Woody and Finian explain that there is no need to dig the gold up, since the news has led to massive investment in their tobacco label. Buzz and the Sheriff, however, accuse Sharon of using witchcraft to turn the Senator black. Woody orders them off. He and Sharon agree to marry ("Old Devil Moon [Reprise]"). Susan the Silent watches them, and dances by herself, and discovers the hidden gold ("Dance of the Hidden Crock"). She takes the gold for herself and hides it.  Meanwhile, the still-black Senator Rawkins is hiding in the woods. He meets Og and explains what happened to him. Og decides what the Senator needs is a new inside rather than a new outside. He uses his own magic to make the Senator a nicer person ("Fiddle Faddle"). In his new persona, Rawkins falls in with a group of black gospel singers looking for a fourth man ("The Begat"); by chance, they are all going to sing at Woody and Sharon's wedding. The wedding is interrupted by Buzz and the Sheriff, who have come to arrest her for witchcraft. The Senator tries to defend them, but as a black man the Sheriff has no need to heed him. Finian steps in, promising Sharon can change the Senator back. He dismisses everyone, intending to use the Crock to undo her wish, but finds the crock gone.  Og, now almost human, looks for Sharon to tell her his feelings. He finds Susan instead, but realizes he is also attracted to her. He wonders if all human love is so fickle ("When I'm Not Near the Girl I Love"). Finian finds them and tells them Sharon is in danger. When Og reveals he doesn't have the gold, Finian runs off in despair. Susan knows where the gold is, but can't speak. Frustrated, Og wishes she could talk, not knowing the gold is under his feet. Susan speaks, and tells him she loves him. Og realizes there is only one wish left, and if he uses it to save Sharon he cannot be a leprechaun again. He is unsure what to do until Susan kisses him. Deciding being human isn't so bad, Og wishes the Senator white again.  The Senator promises to be a better representative to the people, and the Sharecroppers welcome Og and the now-verbal Susan ("If This Isn't Love [Reprise]"). Finian, however, has lost the crock and his hope of getting rich. Seeing that Sharon and Og have found their dreams, he goes off again in search of his own rainbow, saying 'Maybe there's no pot of gold at the end of it, but there's a beautiful new world under it.' The cast tells him goodbye, promising to see him in Glocca Morra ("Finale").

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Finian's Rainbow