'I Am Ali' trailer previews 'intimate' film

A new documentary on famed fighter Muhammad Ali promises to paint "an intimate portrait" of the Louisville native and former heavyweight champion.

The "I Am Ali" trailer posted this month ahead of the film's Oct. 10 release -- both in theaters and on demand -- delivered with snippets of audio recordings, some of which were provided by Ali's family.

"My father has a lot of sides," his daughter, Maryum, recently told ET Online. "You hear about the fights. You don't hear about family that much and what that meant to him."

Another daughter, Hana, told ET Online that they received the tapes from their father in the 1970s. He'd recorded them playing, talking on the phone and even on the way to school.

As Ali's fight with Parkinson's continues, Hana said she calls her father mostly in the mornings, "when he's at his best. His voice is clearer, speaks slow but you can hear him. He has family around him and he's enjoying life."

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