The book is a sprawling narrative that intertwines two timelines: the first during World War II, focusing on the efforts of cryptographers and mathematicians working to break Axis codes, and the second in the late 20th century, following a group of entrepreneurs and hackers establishing a data haven in Southeast Asia. The novel explores themes of cryptography, mathematics, and the history of computing, weaving together real historical figures with fictional characters. As the plot unfolds across different continents and eras, it delves into the impact of information technology on society and the perpetual conflict between governments and individuals over the control of information and privacy.

"Tree of Smoke" is a war novel that explores the chaos, violence, and moral ambiguity of the Vietnam War. The story follows a diverse cast of characters, including a CIA operative, a young soldier, and a pair of missionaries, all of whom are trying to navigate the uncertainties and horrors of the war. The novel delves into themes of faith, fate, and the human capacity for both good and evil, offering a gritty and complex portrait of a turbulent period in history.