The story centers on a family of five orphaned children, two of whom are twins. Phil Daring works in a bank; when he is unjustly suspected of thievery, his twin sister Phoebe, a spirited 16-year-old, seizes the initiative in proving his innocence. (Baum was simultaneously writing a similar story, of a brave girl defending and supporting her brother, in his 1911 novel
The Flying Girl. And he would re-use the plot of a girl with an unjustly-accused relative in his 1916 book,
Mary Louise, the first book of yet another series.) The Daring Twins' late father had been in the sugar business; he was ruined financially when he refused to join in a monopoly, believing that trusts and monopolies are "unjust and morally unlawful" — an interesting look into Baum's values. ==Trivia==