Underground asylum, the

MARK CONLAN, and his son, JESSE, buy a large ranch on a mountain near San Francisco, California. Soon, decapitated murder victims are discovered on and around Mark?s property. Homicide detectives are unable to solve the series of murders. Jesse stumbles upon a vast underground cave/cavern complex on their ranch. Soon thereafter, Jesse is kidnapped. Mark hires a spelunker and they begin to explore the giant caverns. They are immediately attacked by the killer. Mummified heads are found, and signs that Jesse is being held captive in the killer?s dark underground lair. A horrifying game of cat-and-mouse ensues. The murderer is killed--the case apparently solved. Then a surprising mastermind emerges, re-igniting the chase.