The series showcases the defining moments in Ali's life and career - both in and out of the ring - which are well documented, as well as moments that took place away from the spotlight. The world remembers an icon, but The Greatest is about a man, a husband, a father, a brother and a son.

Best plays the boxing legend. Hardwick (pictured, left) plays his father, Cassius "Cash" Clay Sr. Gourrier (pictured, right) plays his mother, Odessa “Bird” Clay.
Former Power actor Hardwick recently appeared in the Paramount+ film Star Trek: Section 31 opposite Michelle Yeoh and in the Netflix film The Mother opposite Jennifer Lopez for Netflix.
Gourrier's recent credits include a recurring role on the AMC series Interview with the Vampire and Starz's P-Valley.
The Greatest is produced by Michael B. Jordan's Outlier Society, which has an overall agreement with Amazon MGM Studios, Watkins' Blue Monday Productions, Authentic Studios, Roc Nation, Polygram Entertainment, a partner of Universal Music Group, and Grace: A Storytelling Company.