Though he was ours — us Watchers, we happy few — for only a short time, he certainly lived a full life. David Carter left his indelible mark on our nation.
As usual for him, Null begins with a frame story that explains how he (Null) came into possession of the text. At the end of the first book, A Princess of Texas, David Carter was unwillingly transported back to Texas. The story proper begins with his arrival back in Midlothian (Texas) after a ten-year separation with Sarah Bresnahan, their unborn child, and the people of the nation of Helium, whom he has adopted as his own. Unfortunately, Carter materializes in the one place in Midlothian from which nobody is allowed to depart: the Valley South, which is the deadlands.
After David Carter's arrival, a boat of tourists on the River Walk are ambushed by the previously unknown Zen Men. The lone survivor is his friend Coz the Shroom, the Busker of Austin, who has taken the pilgrimage to the Valley South to find Carter. Having saved their own lives, Carter and Coz discover that the Utopians, a offshoot of self-proclaimed agnostics, have for eons deceived the Midlothians elsewhere with the lie that the pilgrimage to the Valley South is a journey to paradise. Most arrivals are killed by the beasts who dwell here, and the survivors enslaved or eaten by cannibals.