Jared Leto
Leto is another prolific actor that has changed his appearance multiple times since the beginning of his career. He prides himself on being versatile in all of his roles, but his most versatile to date, according to him, was playing Rayon in Dallas Buyers Club.
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Leto played a transgender woman who was in the process of receiving treatment for HIV. For this role, he dropped 30-40 pounds in a few months. He won a Golden Globe, an Oscar, and a SAG award as best supporting actor that year.