Beyoncé and Sasha Fierce are two very different people.
In a new teaser for her upcoming HBO documentary, Jay-Z's wife reveals her struggle with balancing her professional and private life.
"I always battle with 'How much do I reveal about myself?'" the 31-year-old singer-actress says in a voiceover played over the 25-second clip. Shots of the Dreamgirls star performing on stage are cut together with homemade videos. "If I'm scared, be scared. Allow it. Release it."