In The Wizard of Oz, the Tin Woodman seeks a heart from the Wizard.
The Tin Woodman is a mechanically constructed man who joins Dorothy on her journey to the Emerald City. He believes that becoming metal caused him to lose his heart, so he asks the Wizard to restore it. His desire gives the character one of the film's central emotional goals.
The other travelers have different requests: the Scarecrow wants a brain, and the Cowardly Lion wants courage. These requests are sometimes mixed up because the three companions reach the Wizard together and each receives a symbolic gift.
At the end, the Tin Woodman's compassion shows that he already possesses the quality he thinks he lacks. Jack Haley played the character in the 1939 film, whose production used a famous silver costume rather than the book's original description of tin.