Abandoned by her parents as a child, Bobbye Revels longs for love and security. While she's an awkward player in the game of life, she makes a name for herself playing softball in the city leagues in Atlanta. Upon graduation from high school, Bobbye receives a full scholarship to the University of Georgia to play for the Lady Dawgs and her three closest friends join her there. Stacey Parks, the narrator of Death Cake, is preparing for a career in journalism; long, lanky, easy-going Phil Sanford, the brain of the foursome, is studying engineering; and Tripp MacAvoy, the only child of one of Atlanta's wealthiest families, relishes his role as the consummate bad boy. Stacey and Phil are good buddies, but Bobbye and Tripp have been besotted with each other since the day they met in sixth grade.
Because Tripp is a party animal with unlimited resources, he and his friends host costume parties featuring buffets overflowing with alcohol, bright little blue and red pills, weed-infused brownies, and tantalizing lines of snowy cocaine. As Stacey tells the reader, "We were very popular." On dreary winter weekends, the group holes up on Tybee Island at the MacAvoy beach house where they don costumes and dabble in pornography. In the spring of their sophomore year Tripp's beloved mother dies, and he spirals out of control in his abuse of alcohol and drugs. Following a particularly raucous night, he's arrested. After a judge revokes his driver's license and orders him to pay a heavy fine, Tripp's widowed father, Ed, takes him home to Atlanta and puts him to work in one of the family's textile plants. Tripp despises his job, his co-workers, his father's constant nagging. He buys a plane ticket and disappears.
Two years later, Bobbye, Stacey, and Phil graduate from UGA and move back to Atlanta where Bobbye and Stacey share an apartment. While Bobbye attends graduate school in physical therapy, Stacey and Phil settle into jobs. Stacey, who has been in love with Bobbye since childhood, is extremely happy because Bobbye has not heard from Tripp. In the meantime, Tripp's father, Ed, marries a young flautist with the Atlanta Symphony who knew Bobbye, Stacey, and Phil when they were in high school band. The three of them attend the MacAvoy wedding and, in the months following, are included in events at the couple's elegant home in Virginia Highlands and invited on cruises aboard Ed's yacht, "Mac the Knife."
Tripp emerges from the jungles of South America and returns to Atlanta where he's stunned by the news that his dad is married to a much-younger woman who's sleeping in his mother's bed, playing his mother's Steinway grand, even wearing his mother's jewelry. He and Ed get off to a rocky start, but eventually Tripp moves in with his dad and stepmother, goes to work at the textile plant, and resumes his role as "party master" with his old pals Bobbye, Phil, and Stacey.
Tripp and Bobbye are inseparable and, within months, engaged. Friends begin planning pre-wedding parties and Bobbye asks Stacey to be her Maid of Honor. But everything comes to a standstill when Ed trips on an icy step, cracks his skull open, and is hospitalized for weeks. Bobbye becomes his physical therapist and, over the long months of his recovery, the two develop a close relationship. Meanwhile, Tripp begins a torrid affair with his glamorous stepmother. When Ed is forced to declare bankruptcy and, subsequently, asks Bobbye to serve as a witness to his last will and testament, things turn deadly.
