Buddy Levy, a writing professor at Washington State University since 1988, has made a return to the History Channel, appearing on two shows. He previously cohosted the program “Decoded” in 2010 and is now featured on “The UnXplained with William Shatner” and “History’s Greatest Mysteries” hosted by Laurence Fishburne. In his latest appearance on “History’s Greatest Mysteries,” Levy discusses his book, “River of Darkness,” which explores the journey of the first European explorers into the Amazon. Additionally, in an episode of “The UnXplained,” he examines two secret societies: Yale University’s Skull and Bones and the Bohemian Grove in Northern California.