In the early 20th century “Madam” C.J. Walker, born Sarah Breedlove, worked her way up from washerwoman to millionaire, courtesy of the line of hair-care products she developed for her fellow black women. Too bad that in this hagiographic melodrama, writer-director Regina Taylor reduces the fascinating Walker to an African-American Mildred Pierce. Taylor’s parade of (offstage) historical names can’t raise the script above the level of a generic tale about a plucky woman who succeeds in business but struggles with relationships, particularly with her headstrong party-girl daughter. As director, Taylor fails to vary the plodding pace of this two-and-a-half-hour show, and even mesmerizing actor L. Scott Caldwell as Walker delivers only grandstanding bravado, not emotional subtlety. Through 7/23: Wed 7:30 PM, Thu 2 and 7:30 PM, Fri 8 PM, Sat 2 and 8 PM, Sun 2 PM, Sun 7/2, 2 and 7:30 PM, Sat 7/1, 8 PM only, Goodman Theatre, 170 N. Dearborn, 312-443-3800, $20-$65.