When I heard Rob Reiner was planning to direct a documentary on a true comic icon and genius named Albert Brooks, I thought “Now this will be good!” Reiner is not only a smart and talented filmmaker in his own right, but also a longtime friend of Brooks, with whom he went to high school and even co-starred with him in drama department productions. I am happy to report this HBO Original documentary, Albert Brooks: Defending My Life, premiering Saturday night and then streaming on Max, not only more than met my high expectations but exceeded them.

Set in a plush dark red restaurant booth, the film is anchored simply by a conversation between Reiner and Brooks. The visual is almost identical to the opening scene of Brooks’ 1981 Modern Romance, where he and his girlfriend are breaking up,...