In 1939, Hamilton played the role of the Wicked Witch of the West, opposite Judy Garland's Dorothy Gale in The Wizard of Oz, creating, not only her most famous role, but also one of the screen's most memorable villains.
Hamilton was cast after Gale Sondergaard, who was first considered for the role, albeit as a more glamorous witch with a musical scene, declined the role when the decision was made that the witch should appear ugly.

She suffered a second-degree burn on her face and a third-degree burn on her hand during a second take of her fiery exit from Munchkinland in which the trap door's drop was delayed to eliminate the brief glimpse of it seen in the final edit.
Hamilton had to recuperate in a hospital and at home for six weeks after the accident before returning to the set to complete her work on the film and refused to have anything further to do with fire for the rest of the filming.
After she recuperated, she said, "I won't sue, because I know how this business works, and I would never work again.
I will return to work on one condition – no more fireworks!"
Garland visited Hamilton while the latter recuperated at home looking after her son.
 Studio executives cut some of Hamilton's more frightening scenes, worrying they would frighten children too much.
Later in life, she would comment on the role of the witch in a light-hearted fashion.
During one interview, she joked:
I was in need of money at the time, I had done about six pictures for MGM at the time, and my agent called.
I said, 'Yes?'
and he said 'Maggie, they want you to play a part on the Wizard.'
I said to myself, 'Oh, boy, The Wizard of Oz!
That has been my favorite book since I was four.'
And I asked him what part, and he said, 'The Witch,' and I said, 'The Witch?!'
and he said, 'What else?'

Hamilton's stand-in and stunt double for the Witch, Betty Danko, also suffered an on-set accident on February 11, 1939.
Danko made the fiery entrance to Munchkinland, not Hamilton.
She was severely burned during the "Surrender Dorothy!"
skywriting sequence at the Emerald City.
Danko sat on a smoking pipe configured to look like the Witch's broomstick.
The pipe exploded on the third take of the scene.
She spent 11 days in the hospital and her legs were permanently scarred.
The studio hired a new stunt double, Aline Goodwin, to finish the broomstick-riding scene for Danko.

When asked about her experiences on the set of The Wizard of Oz, Hamilton said her biggest fear was that her monstrous film role would give children the wrong idea of who she really was.
In reality, she cared deeply about children, frequently giving to charitable organizations.
She often remarked about children coming up to her and asking her why she had been so mean to Dorothy.
She appeared on an episode of Mister Rogers' Neighborhood in 1975 where she explained to children she was only playing a role and showed how putting on a costume "transformed" her into the witch.
She also made personal appearances, and Hamilton described the children's usual reaction to her portrayal of the Witch:
Almost always they want me to laugh like the Witch.
And sometimes when I go to schools, if we're in an auditorium, I'll do it.
And there's always a funny reaction, like 'Ye gods, they wish they hadn't asked.'
They're scared.
They're really scared for a second.
Even adolescents.
I guess for a minute they get the feeling they got when they watched the picture.
They like to hear it but they 'don't' like to hear it.
And then they go, 'Ohhhhhhhhhh ... !'
The picture made a terrible impression of some kind on them, sometimes a ghastly impression, but most of them got over it, I guess ... because when I talk like the Witch, and when I laugh, there is a hesitation and then they clap.
They're clapping at hearing the sound again.

Hamilton played two credited roles in the famous film: Almira Gulch and the Wicked Witch of the West.
Hamilton also appears as an unidentified flying witch during the tornado scene, which may have been the Wicked Witch of the West or her sister, the Wicked Witch of the East.
If the latter case,
In 1939, Hamilton played the role of the Wicked Witch of the West, opposite Judy Garland's Dorothy Gale in The Wizard of Oz, creating, not only her most famous role, but also one of the screen's most memorable villains. Hamilton was cast after Gale Sondergaard, who was first considered for the role, albeit as a more glamorous witch with a musical scene, declined the role when the decision was made that the witch should appear ugly.
She suffered a second-degree burn on her face and a third-degree burn on her hand during a second take of her fiery exit from Munchkinland in which the trap door's drop was delayed to eliminate the brief glimpse of it seen in the final edit. Hamilton had to recuperate in a hospital and at home for six weeks after the accident before returning to the set to complete her work on the film and refused to have anything further to do with fire for the rest of the filming. After she recuperated, she said, "I won't sue, because I know how this business works, and I would never work again. I will return to work on one condition – no more fireworks!" Garland visited Hamilton while the latter recuperated at home looking after her son.  Studio executives cut some of Hamilton's more frightening scenes, worrying they would frighten children too much. Later in life, she would comment on the role of the witch in a light-hearted fashion. During one interview, she joked:
I was in need of money at the time, I had done about six pictures for MGM at the time, and my agent called. I said, 'Yes?' and he said 'Maggie, they want you to play a part on the Wizard.' I said to myself, 'Oh, boy, The Wizard of Oz! That has been my favorite book since I was four.' And I asked him what part, and he said, 'The Witch,' and I said, 'The Witch?!' and he said, 'What else?'
Hamilton's stand-in and stunt double for the Witch, Betty Danko, also suffered an on-set accident on February 11, 1939. Danko made the fiery entrance to Munchkinland, not Hamilton. She was severely burned during the "Surrender Dorothy!" skywriting sequence at the Emerald City. Danko sat on a smoking pipe configured to look like the Witch's broomstick. The pipe exploded on the third take of the scene. She spent 11 days in the hospital and her legs were permanently scarred. The studio hired a new stunt double, Aline Goodwin, to finish the broomstick-riding scene for Danko.
When asked about her experiences on the set of The Wizard of Oz, Hamilton said her biggest fear was that her monstrous film role would give children the wrong idea of who she really was. In reality, she cared deeply about children, frequently giving to charitable organizations. She often remarked about children coming up to her and asking her why she had been so mean to Dorothy. She appeared on an episode of Mister Rogers' Neighborhood in 1975 where she explained to children she was only playing a role and showed how putting on a costume "transformed" her into the witch. She also made personal appearances, and Hamilton described the children's usual reaction to her portrayal of the Witch:
Almost always they want me to laugh like the Witch. And sometimes when I go to schools, if we're in an auditorium, I'll do it. And there's always a funny reaction, like 'Ye gods, they wish they hadn't asked.' They're scared. They're really scared for a second. Even adolescents. I guess for a minute they get the feeling they got when they watched the picture. They like to hear it but they 'don't' like to hear it. And then they go, 'Ohhhhhhhhhh ... !' The picture made a terrible impression of some kind on them, sometimes a ghastly impression, but most of them got over it, I guess ... because when I talk like the Witch, and when I laugh, there is a hesitation and then they clap. They're clapping at hearing the sound again.
Hamilton played two credited roles in the famous film: Almira Gulch and the Wicked Witch of the West. Hamilton also appears as an unidentified flying witch during the tornado scene, which may have been the Wicked Witch of the West or her sister, the Wicked Witch of the East. If the latter case, 
Margaret Hamilton (actress)