For a skeptic, the Pacific Northwest, home of the legendary Bigfoot, and birthplace to the modern era of UFO, can sometimes be a busy place... The Unexplained Mount St. Helens is set to erupt again, and a man is found murdered on the volcano's slopes with all clues pointing to Bigfoot as the culprit. Alarmed at the direction the case is taking, FBI Agent Dan Fisher brings in a skeptic to help separate the facts from the fiction. Explained Steve Hanson is an introvert who prefers the seclusion of his home to facing the outside world. But Agent Fisher's request is too amazing to pass up, and would make a remarkable entry into Hanson's blog, The Unexplained, Explained. It also helps his interest when he realizes that Hawaiian volcanologist Makani Batemen is part of the investigation. But something is working against them, and Hanson and Makani find themselves threatened by whoever, or whatever, is behind the killing. Adding to the mystery, local entrepreneur Wayne Kesler, a billionaire with his own Search for Extra-terrestrial Life program, has taken an interest in them. While Agent Fisher leads the search to find a more mundane answer to the murder, Bigfoot attacks Hanson and Makani. Hanson's beliefs are further challenged when he witnesses a UFO in the night sky. With the volcano ready to explode and time running out, Hanson and Makani realize that they are in a fight for their lives. And before they can reveal the truth they will have to face off against the U.S. military's most advanced weapon to stop a plot that could tear the nation apart, and change the balance of world power, forever.