In March 2009, Rhonda Casto plunged to her death from a 300-foot cliff in the Oregon woods. The only witness, Stephen Nichols, the father of her nine-month-old baby, Annie, told police investigators she slipped and fell. Yet, Nichols' story didn't mesh with the facts. And some of his other actions raised suspicions as well, including just days after her death trying to collect on a million-dollar life insurance policy he'd taken out on his unemployed, 23-year-old girlfriend. What had begun with a 911 call to report an accident, quickly turned into a homicide investigation.