The Turner family had always lived at Grangely Hall in North Yorkshire. William and his wife adopt his dead sister's daughter, Alexandra Shankland, who Ernestine, the wife, calls a door-step baby.

Marianne, their daughter, is set to marry the son of one of William's friends, Ralph, for the financial good of both families. Alexandra persuades their cook to teach her to bake, for feeding the poor, and when Ralph visits he accompanies her on her charitable visits.

After William has a heart attack he tells his son that due to lack of funds the estate must be sold. But Alexandra determines to find out more about investment in the iron industry.

Her aunt contracts cholera, and Marshal follows Marianne to London to check on her health and she is found to be pregnant. Ernestine dies leaving Marianne as mistress of her family home.

She invents scenes of madness for Alexandra and she is sent away to an estate cottage, where she discovers she is the heiress of the well-to-do Neville family, because Shankland was not her true father, his employer was. Eventually, after causing more trouble, Marianne is sent packing by Marshal, so Alexandra and Marshall can now marry.

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