The Valles Caldera in New Mexico is the setting for Book Two of the Angus series of novels. More than a million years ago, a volcanic eruption created a 13-mile wide enclosed caldera filled with water. High mountain peaks formed from ring fractures dominate the caldera. It became a life sustaining place for generations of Indians, Hispanics, and Anglos. This novel is about the epic battle between U.S. Marshal, Angus Esparazza, and a bad hombre named Mendoza-Mendoza, on the rim of the Valles Caldera. Mendoza and his men were tracking Angus up the Rio Grande to the confluence of the Rio Chama looking for a kill shot. Earlier, Angus had insulted Mendoza's chest-pumping sons in the little village of Bernalillo. That insult came from the muzzle of Angus's custom-made, .45 caliber, Colt single-action pistol. Angus was not after Mendoza or his boys; he was investigating one of New Mexico's most famous legal cases--the hanging of Albuquerque Town Marshal Milton J. Yarberry in 1885. Yarberry, one of the state's most colorful historical characters, was hung by the "jerk method" in downtown Albuquerque. After witnessing that grim event, Angus meets Jill Garrison, a fictional character, who changes him in ways he could never have imagined. She was New Mexico's first female gunsmith and its first high-end shooting instructor. In the end, Angus and a seven-man mounted posse cross the Rio Grande at Santa Fe to arrest Mendoza and his men. They ride all the way across the M/ ranch to the upper rim of the Valles Caldera. There, all hell breaks out.