Radio astronomers discover a mysterious signal in the deep sea that could be contact with extraterrestrials. After several terrifying manifestations threaten their beliefs, the team must fight to survive the ultimate evil.

For their honeymoon, newlyweds Cliff and Cydney head to the tropical islands of Hawaii. While journeying through the paradisaical countryside the couple encounters Kale and Cleo, two disgruntled hitchhikers and Nick and Gina, two wild but well-meaning spirits who help guide them through the lush jungles. The picturesque waterfalls and scenic mountainsides quickly give way to terror when Cliff and Cydney learn of a grisly murder that occurred nearby and realize that they're being followed by chance acquaintances that suspiciously fit the description of the killers.