News Ken Burns’ PBS Muhammad Ali four-part documentary gives an expansive look at boxing legend’s life September 15, 2021September 15, 2021Scooby Axson, USA TODAYComments Off on Ken Burns’ PBS Muhammad Ali four-part documentary gives an expansive look at boxing legend’s life 'Muhammad Ali,' which will be shown on PBS for four nights starting Sept. 19, was a labor of love that uncovers more about the boxing legend.