In 2011, Robyn Gardner left Maryland for what was supposed to be a relaxing getaway in Aruba with a man she barely knew. Just two days into the trip, she vanished without a trace during what he claimed was a snorkeling excursion gone wrong. But from the moment authorities began investigating, nothing added up. As suspicions mounted and disturbing evidence surfaced, one question remained: what really happened to Robyn Gardner on that beach in Aruba?