Dan and Isaac are back from searching through the wreckage of Eastern Airlines Flight 980 on a remote mountain in Bolivia, but their findings have prompted a whole new set of questions. Will anyone look at the material they brought back to the U.S.? Who hired climber Bernardo Guarachi to get to the crash site back in 1985? And why did he never speak to anyone about his ascent? Have the details of the crash remained a mystery because of international cover up or just bad weather and bad luck?