Carey Mulligan quickly racked up an impressive list of credits in her 20s. She was just 24 when she was nominated for her first Oscar for her performance in "An Education." When she wasn't appearing in starring roles in big-budget films like "Shame," "Drive," and "Far From the Madding Crowd," she was back on stage.

In fact, as Mulligan confessed to The Times, she was a bit of a workaholic. "I used to freak out if I didn't have back-to-back work lined up," she said.

When she wasn't on set or on stage, Mulligan was preparing for her roles, scribbling letters, poems, and artwork into notebooks. As she went on to explain, research became a big part of her process. For her role in "The Great Gatsby," she said, she did "months of research." As Mulligan explained, this workaholic mentality developed out of imposter syndrome. "I didn't get into drama school, I didn't go to university, so this was my homework," she said.