In 1978, a young British couple embarked on the trip of a lifetime through remote Central America. Chris Farmer and Peta Frampton set out on an exhilarating backpacking adventure, but their dream soon turned into a chilling nightmare when they were brutally murdered and the trail for their killer goes cold. Four decades later, failed by law enforcement, their family take up the manhunt and begin the descent into an unknown world of online sleuthing, making a shocking discovery.