"The Thirteenth Letter" by Natalie Sumner Lincoln is a murder mystery novel written in the early 20th century. The narrative opens with an ominous atmosphere surrounding Paul Abbott, a sick man who has just returned home to his family's country lodge near Washington, D.C. The story unfolds as the focus shifts to his nurse, Miriam Ward, whose fateful night shift becomes intertwined with the shocking events that follow Abbott's apparent murder. At the start of the story, Paul Abbott is gravely ill, and his new nurse, Miriam Ward, is tasked with his care amid a raging snowstorm. As events transpire, a mysterious girl named Betty Carter arrives with a clergyman, ultimately revealing a complex web of relationships. Tension builds when Abbott is discovered dead, leading to chaos and intrigue. As the characters grapple with confusion and suspicions, Miriam's night takes a dark turn when she finds herself chloroformed, complicating her role in the unfolding mystery. This opening effectively sets the stage for a gripping tale of deception, love, and the quest for justice. (This is an automatically generated summary.)