Sweet and Deadly is the first novel by mystery writer Charlaine Harris. It is a novel of secrets and murder with a little romance thrown in for good measure. The heroine of the novel, Catherine Linton, is in the depth of depression after the loss of her parents. On an innocent afternoon excursion, Catherine finds the dead body of a family friend, an event that drags her from her self -mposed isolation. Catherine is convinced the death of this woman is connected to the deaths of her parents, and she is determined to find the culprit. Sweet and Deadly is a mystery full of Southern charm that will delight readers of all ages.

Catherine drives outside town to spend a Saturday morning shooting her gun when she finds the dead body of her father's nurse. Catherine is in a state of shock until the next morning when it occurs to her that this murder could be related to the death of her parents. Catherine's parents died six months previously when someone tampered with their car. However, the sheriff does not think the two episodes are related, leaving Catherine with the idea that there could be two murderers lose in her small town. The sheriff tells Catherine that the nurse was blackmailing people in town and that she may have taken medical equipment from Catherine's father's office. Catherine later learns that this equipment had been used for the nurse to perform abortions. This information forms a motive, leaving Catherine taking a closer look at the people she has known all her life, wondering how many of them have secrets they would kill to hide.

Catherine returns to work on Monday, after spending much of the weekend with her boss, Randall. Catherine works for the newspaper. Her fellow reporter, and tenant, Tom, is charged with writing the story on the discovery of the body. Tom is fresh out of journalism school and excited to finally have a story to write that has some teeth to it. However, Tom has trouble getting anyone to talk to him, especially the sheriff. This does not stop Tom. Tom continues to annoy everyone in town trying to find out who killed the nurse.

Old friends of Catherine's come out of the woodwork over the next few days. First a neighbor, Miss Molly, brings a casserole to Catherine in a thinly veiled attempt to get fodder for gossip. When Catherine returns the dish, she spends a nice evening with Miss Molly and her husband, Carl. Carl is concerned for Catherine, worried about how isolated her house is. Carl insists on walking Catherine home. When he drops her off, Carl asks about the medical records her father left behind, and Catherine tells him they are in the attic of her father's office, the house that Tom rents. Another friend, the local librarian, visits Catherine and also expresses concern about Catherine's safety.

A few nights later, Catherine is home alone doing some housework when the buzzer between Tom's house and Catherine's begins to ring. Catherine thinks it is a joke on Tom's part at first, but decides to investigate. Catherine walks into the house and finds Tom badly beaten. He dies while Catherine is checking his pulse. The sheriff is called and his first thought is that Catherine is responsible, but no one really believes that Catherine is strong enough to beat a young man like Tom to death.

While making her statement on Tom's death, Catherine is urged to visit her family's old maid, Betty. Catherine makes the visit and learns that three days before her father's death, Betty overheard her father having an argument in his office with an unknown man. Later, Catherine takes this information and puts it together with a few other small clues and figures out who the killer is and why. Catherine thinks her neighbor, Carl Perkins, has leprosy, that her father diagnosed it, and that her father had insisted on reporting it to the health officials. Carl did not want this to happen, so he killed Catherine's father to keep it from happening. Later, the nurse, who had also overheard the conversation, began blackmailing Carl. Carl killed her in an attempt to stop the blackmail, but he was unable to find the evidence. Catherine knows the evidence is in Carl's medical file at Tom's house and this is why Carl killed Tom.

Catherine goes to Tom's house and retrieves the file. However, when she climbs down from the attic, Catherine finds Carl waiting for her. Catherine runs away, but Carl is close on her tail. Catherine runs out into the street, remembering her gun that she has had with her the whole time. Catherine turns, takes aim and fires, but misses. Catherine fires again and kills Carl.