When Marie Benedict researches her historical novels, she resembles Indiana Jones, she says. In her words, she is "excavating the past." Thanks to Benedict's books, I've dug into the lives of Clara Kelley, a fictional Irish maid in Pittsburgh in the 1860s; Belle da Costa Greene, the remarkable African-American book-and-art acquisitions specialist who worked for J.P. Morgan in New York City in the early 1900s; and the beautiful actress Hedy Lamarr, who was also a World War II scientist and inventor in Vienna and Hollywood.