Tree of Smoke is a 2007 novel by American author Denis Johnson which won the National Book Award for Fiction and was a finalist for the Pulitzer Prize. It is about a man named Skip Sands who joins the CIA in 1965, and begins working in Vietnam during the American involvement there. The time frame of the novel is from 1963 to 1970, with a coda set in 1983. One of the protagonists of Tree of Smoke is Bill Houston, who was the main character in Johnson's 1983 debut novel Angels. There are several references in the novel to the title phrase, which has Biblical origins in three cited passages: Song of Solomon 3:6; Book of Joel 2:30, 31; and Exodus 33:9, 10. Source: Wikipedia (en)