The Ghosts of Petroglyph Canyon

School is out for the summer and Pablo Perez, his sister, Pia, and their cousin, Kiki Flores, visit the Bar-7 ranch in New Mexico. The young Missourians have come to help their Uncle Antonio with the annual cattle roundup. Uncle Antonio introduces his nephew and nieces to hundreds of primitive petroglyphs that have been chiseled into the walls of a nearby canyon. Sadly, looters are routinely excavating the ancient drawings with high-tech rock saws. Uncle Antonio believes the looters are selling the glyphs. Pablo, Pia, and Kiki are determined to put a stop to the looting, and that's when the adventure begins.