Arabella Tucker and her sister Nan arrive in London in 1756 to try and find themselves husbands. Although from an aristocratic background, their father's loss of fortune means he can no longer provide for them and they must find another man to do so. While Nan immediately sets her sights on an older but extremely wealthy bachelor, Arabella is not content to marry a man purely for his money. Everyone expects the handsome Gervase Roxbourne to propose, but she firmly believes in true love and is sure she can find a husband who will both provide for her financially and satisfy her romantic desires. Nan marries her wealthy lord and soon provides him with a much-needed heir. Meanwhile, Arabella falls for the handsome Lord Harry Sylvester, a gambling rogue who promises her much but almost inevitably fails to deliver. When Harry's many creditors finally catch up with him and he is sent to the dreaded debtors' prison, Arabella finds herself pregnant and alone. Having committed the ultimate sin, she is now a fallen woman, improverished and cast out of society. What lies ahead for Arabella now that Harry has deserted her? Will Gervase take pity on her by becoming her protector? Or will the wilful Arabella insist on following her romantic notions to their inevitable, dangerous conclusion?