11-year-old Maud Flynn gets whisked away from a cold New England orphanage and into the stately mansion of three wealthy spinsters. After the Hawthorne sisters adopt her in 1909, they tell her she's their secret child. She must remain indoors at all times and must never stand in front of windows. Since these old ladies treat her so well, Maud doesn't mind their restrictions. But she does wonder what could require such secrecy.