Plot Synopsis of The Wife and the Mistress, a novel in four volumes by Mary Charlton by Elizabeth Dowen McKie

When the Marquis of Bellingham marries Lady Emily Melville, he has to forsake his mistress, Laura Delaunie, and their illegitimate child. Laura is persuaded to move away with her daughter (who is named after her mother) by Emily’s manipulative and domineering mother, the widower Lady Melville.

Emily has been taught since childhood by Lady Melville to be the perfect Society Belle, in the hope that if she could assure Emily’s marriage to an esteemed gentleman, then she would regain some of her own status in society. However, her influence has made the once innocent Emily spoilt, superficial, and extravagant. The Marquis becomes concerned about Emily’s debts, and in an attempt to placate him Emily proposes that Laura comes to live with them.

Although Laura’s mother is extremely distressed to let her go, she is forced to agree. Under the influence of her father’s family, Laura becomes spoilt and ill-mannered. When her mother is finally allowed to see her, she is so shocked at how greatly her daughter has been altered, that she refuses to allow Laura to return. The Marquis decides to visit them, and to restart his affair with Laura’s mother, but she virtuously rejects him. In spite of this, he demands that Laura returns to his home, to remain there until he decides otherwise. She is then told (untruthfully) that her mother is dead..

Laura resides with the Bellinghams until Emily becomes pregnant several years later. No longer the Marquis’s only child, she is sent away, and after a short stay with a disreputable family, the Balliochs, she is allowed to live with her mother, who is now respectably married to Mr Rothmere. This is agreed to, on the condition that she pretends to be a friend of Laura’s ‘deceased’ mother. Laura soon comes to love and respect Mrs Rothmere, and under her patience instruction she is instilled with modesty, humility, and propriety. She lives with Mrs Rothmere, and her immature husband, until she is seventeen, and the Marquis demands that she returns to him to make her entrance into society. The worry of her daughter’s departure, coupled with the increasingly irresponsible behaviour of Mr Rothmere, causes Mrs Rothmere’s health to fail, and she dies.

When Laura goes to stay (accompanied by her maid, Dolly) with the Bellinghams, she shocked by the indecorous behaviour displayed by the household and their fashionable associates. She is also distressed because her family encourage the advances of several men in the group, in the hope of getting her ‘suitably’ married to their own benefit. Her only true friends there are Mr and Mrs Aubrey, at the Rectory (who she is discouraged to associate with, due to their lower social status), and Lord John Traherne. At the Rectory she also meets and befriends Caroline and Cecil St. Orme, a brother and sister of her own age.

Emily then runs away with Mr Averne, causing great scandal and distress for her family who all go to search of her. The Marquis summons Laura to London, where she is placed in Mrs Meedon’s house for genteel young ladies, before he leaves town. Lord John also leaves town, but before he does this he informs Laura that he will help protect her from the Bellinghams, in honour of his beloved deceased son, who was greatly attached to Laura’s mother, many years before. He is also impressed with Laura’s ‘truly unadulterated mind’. Whilst at Mrs Meedon’s, Laura becomes close friends with Mrs Meedon's down-trodden daughter, Fanny. The Marquis soon stops paying for Laura’s board and she is asked to leave. Isolated from her friends, she is forced to accept the hospitality of Lady Melville. Lady Melville schemes to encourage the rich, but disreputable, Lord Glendarvon's intentions towards Laura. She tries to convince Laura that she should accept her guidance, by telling her that Mrs Rothmere was actually her mother, and that she thought Lady Melville was a suitable guardian. Laura begins to doubt herself, particularly as her correspondence is restricted and she has no one to ask advice from. Emily then returns to her mother, distraught and penniless, but Lady Melville refuses to assist her in her disgraced state. Soon after, Emily, driven to distraction by her situation, commits suicide.

When Lady Melville tries to coerce Laura into marrying Lord Glendarvon, she bravely runs away. She is finally reunited with the Aubreys, and St. Ormes. They discover that their letters were being intercepted, and all misunderstandings are resolved. Laura discovers that although Lord John is still away, his sister, Lady Betty Traherne, wants to offer her patronage. This she accepts, and although Lady Betty is very old-fashioned and strict, she offers her genuine protection and support. As she is now allowed contact with the Aubreys and their friends, she increasingly comes to admire innocently the gentlemanly Cecil St. Orme. He reciprocates her feelings, and after an averted attempt of Lady Betty’s to marry Laura to her godson, proposes to her. Lord John arrives in time to convince Lady Betty of the suitability of the situation, thus confirming that they will happily supply Laura’s dowry. The happy couple are soon married, to their own and their friends’ rejoicing.