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Margaret Hamilton, on the roof, awaits her cue while Jack Haley's Tin Man has a heart-to-heart with Dorothy and the Scarecrow.
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Lions and tigers and bears, oh my! The trio (plus Toto, whose real name was Terry) approaches the Cowardly Lion's hunting grounds.
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Judy Garland, 16, was initially considered too old and too tall for Dorothy. MGM wanted 10-year-old Shirley Temple instead.
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Ray Bolger was initially approached to play the Tin Man, but he lobbied hard to play the rubber-legged Scarecrow.
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Jack Haley was the last one to join the cast. He replaced Buddy Ebsen two weeks into filming after the original Tin Man fell ill from the character's aluminum dust makeup.
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Bert Lahr was a vaudeville star famous for playing anxious and neurotic comic characters. He was perfect for the Cowardly Lion.
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Frank Morgan got the role of the Wizard after W.C. Fields demanded too much money. Fields' Wizard would've been more of a con-man while Morgan played him as a frightened little humbug.
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The men who were hired to play the winged monkeys were attached to ''bat wings'' and a small motor suited to power windshield-wipers.
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Harry Earles, Jerry Maren, and Jackie Gerlich, who became the Lollipop Guild kids in Munchkinland. Maren, now 94, is the last surviving Munchkin actor.
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Margaret Hamilton was a character actress who played a lot of housemaids. Her performance as the Wicked Witch would frighten generations of children, who routinely cowered when they met her in person.
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Victor Fleming consults with his actors. Fleming was one five directors who worked on Oz, but he left before it finished to take over Gone With the Wind.
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Fleming with actors Billy Curtis (left) and Charlie Becker (right). Stories of randy Munchkinland behavior, like the anecdotes Judy Garland told frequently in her later years, were more publicity than reality.
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Bolger mugs with Mickey Rooney, the MGM star of the Andy Hardy movies who was Garland's frequent costar.
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The MGM Optical Department photographed the film's titles.
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Casting Garland was a risk, but no one ever doubted her voice. Curiously, her signature song, ''Somewhere Over the Rainbow,'' was nearly cut from the film.
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Blanche Sewell edited The Wizard of Oz, an enormous responsibility considering all the scenes that were ultimately discarded.
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Producer Mervyn LeRoy helped persuade MGM's Louis B. Mayer to acquire the rights to L. Frank Baum's book and played a crucial role in the casting of the characters.
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The film opened in New York on Aug. 17, 1939. With Judy Garland and Mickey Rooney hosting screenings at Loew's Capitol Theater, it set house records.
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Aug. 15, 1939: The west-coast premiere of The Wizard of Oz at Grauman's Theater in Los Angeles. Though the film opened strong, it wouldn't earn its money back until 1948.