Upon the death of his beloved mother, half-Italian, half-English nobleman Louis Mazzini resolves to seek revenge upon his estranged aristocratic family for ostracising her for marrying for love, and for denying his existence.

Through a series of plots and happy coincidences, Mazzini brings about and observes the demise of an array of members of the family he has never met, edging ever-closer towards becoming the Duke of Chalfont himself.

Meanwhile, the softly-spoken former department store clerk is taunted by Sibella, his beguiling and manipulative childhood sweetheart who married another man despite his warnings, and is now deeply regretful of her choices.