US comedian Chris Rock's documentary about African American hair culture (opening US-wide October 23) tries to clear up the difference between "good" and "bad" hair.

Prompted by his daughter Lola's question why she didn't have "good" (as in "relaxed and nice," according to one woman in the movie) hair, Rock went on a quest to find out what is in and on black women's heads in the US.

He visits hair salons and styling battles across the country, scientific laboratories, and even India where most imported human hair for wigs and weaves is imported from, touching upon African-American grooming ("It's kinda like a torture session.") but also black self-esteem ("So my nappy hair isn't worth anything?") and sexual relationships ("Sex with a weave is a little awkward.").

Good Hair features guest appearances by celebrities such as Ice-T, Kerry Washington, Nia Long, Paul Mooney, Raven Symoné, Maya Angelou, and Reverend Al Sharpton and discloses the secret of Salt'n'Pepa's shaved-off hairstyle -- it was accidentally burned off at a salon.