In 1859, Nell goes to live with her aunt, Kate Warne, a female detective for Pinkerton's National Detective Agency, and helps her aunt solve cases, including a mystery surrounding Abraham Lincoln and the mystery of what happened to Nell's own father.
Chicago (Ill.) -- History -- 19th century -- Fiction.
Detective and mystery stories.
Lincoln, Abraham, 1809-1865 -- Fiction.
Orphans -- Fiction.
Pinkerton's National Detective Agency -- Fiction.
Sex role -- Fiction.