Playing substitute for Alex Haley proved to be an irresistible challenge for Tananarive Due.(Chicago Tribune)

At the time of his sudden death in 1992, Alex Haley had amassed boxes of research for a major novel in the tradition of "Roots," the best-selling family saga that riveted Americans during its eight-night run as a television mini-series in the 1970s.

Representatives of Haley's estate searched for a writer to fill Haley's formidable shoes and complete the sweeping historical novel he envisioned about Madame C.J. Walker, the uneducated daughter of former slaves who worked her way up from laundress to wealthy founder of a hair-care products company.

They chose Tananarive Due for the daunting job.

A novelist who writes in the supernatural suspense genre and a former Miami Herald feature writer, Due, despite feeling a bit intimidated, accepted immediately.

For either a novelist or a reporter, the larger-than-life Madame Walker, the first black female millionaire, is a . . tantalizing character.

"I thought it was a great story that would almost write itself, " said Due during a recent visit to Chicago.

"She came from such poverty and overcame so much, but what I loved about it was that she started her business so late in life.

"She was in her late 30s, and at the …