The opening pages of the novel follow Pirate Prentice, first in his dreams, and later around his house in wartime London. Pirate then goes to work at ACHTUNG, a top-secret military branch, with Roger Mexico and Pointsman, who both worked there at the time. It is here the reader is introduced to the possibly promiscuous US Army lieutenant named Tyrone Slothrop (at certain points in the book, Pynchon leads the reader to doubt the very existence of the women Slothrop claims to sleep with), whose erratic story becomes the main plot throughout most of the novel. In “Beyond The Zero”, some of the other characters and organizations of the book note that each of Slothrop's sexual encounters in London precedes a V-2 rocket hit in the same place by several days. Both Slothrop's encounters and the rocket sites match the Poisson Distributions calculated by Roger Mexico, leading into reflections on topics as broad as Determinism, the reverse flow of time, and the sexuality of the rocket itself.