In One's Heart of Heart is an 18th Century romantic and mystery novel, set in London, Spittle Fields, 1765. The story begins with the charming heroine, Emily Little, a courageous, intelligent, and wise lady, who gives her account of her unfortunate life to the reader. She appears forlorn and distraught by the many tragedies she encounters, and is a fugitive, along with her most cherished friend, Mildred Brown. Sadly, after Mildred's death, she has no alternative but to seek refuge alone, in a smithery, in Spittle Fields, where she meets a blacksmith named Matthew Taylor, whom she soon falls in love with, after enduring many quarrels with the ill-tempered and rugged blacksmith. Emily suffers many more dangers and conflicts during her incredible journey, meets some strange and amusing characters along the way, and holds many secrets in her heart, that will soon be discovered.