As Tractrix opens, aerospace engineer and recent widower Frank Morton is collecting an USD86 million lottery jackpot. Coincidently, an old Viet Nam buddy shows up with a mysterious black sphere inscribed with what appear to be Maya hieroglyphics. Intrigued, Frank convinces his buddy and two other friends, an anthropologist and a newspaper researcher, to help him investigate the origin and purpose of the sphere. The search leads Frank and friends on a journey from Seattle to the secret military installations of Nevada and on to Mexico's Yucatan Peninsula. Along the way, they attract the unwanted attention of government agents, Mexican Federales and an ancient Maya priest. They also stumble across a three thousand year old secret that suggests a possible link between the shamans of Mesoamerica and a race of alien explorers.