Emma Stone
In the movie Battle of the Sexes, Emma Stone became the tennis pro, Billie Jean King. In order to look the part, Stone underwent extensive training to become the legendary tennis player. She trained under Jason Walsh, a celebrity sports and nutrition coach that put her on a rigorous regimen of exercise, protein shakes, and tennis lessons that would terrify the average person...
Battle-Born
Stone ended up gaining 15 pounds in her training. She also was able to perfectly mimic Billy Jean King's mannerisms, and she beat a couple of tennis players on the way. This transformation ended up landing Stone an Oscar in 2017.