Part 1 of the novel introduces the reader to the Deans family, particularly focusing on Jeanie Deans and her sister Effie. The story is set in Edinburgh, Scotland, in the early 18th century. Effie Deans becomes romantically involved with George Staunton, a man of dubious character, and finds herself pregnant. Unfortunately, Effie is accused of infanticide after her baby mysteriously disappears, and she is imprisoned in the infamous Tolbooth prison, known as the Heart of Midlothian.