When he goes to spend the summer with his great-aunt in the family's old house, eleven-year-old Drew is drawn eighty years into the past to trade places with his great-great-uncle who is dying of diphtheria.
In the nineteenth century, ten-year-old Florence Crutchfield leaves a London orphanage to live with her great-uncle, great-aunt, and sickly cousin James, but she soon realizes the home has another resident, who means to do her and James harm.