It's a gruesome mass murder no one knew about until a 2011 excavation revealed the sinister secret. Discover the story of a pre-Viking warrior tribe that was massacred in Swedish ringfort Sandby Borg and left to rot where they fell. Follow investigators as they piece together what happened 1,500 years ago, using cutting-edge modern forensic analysis. It's a tale of betrayal and power struggles that has haunted the Baltic island of Oland for centuries.

Ancient records marked a modest Tunisian coastal town as the location of a one-time thriving Roman metropolis called Neapolis, but for centuries there was little archaeological evidence to support such a claim. That all changed when a massive storm in 2013 exposed the ruins of ancient streets and buildings beneath the Mediterranean Sea. This discovery reveals the city was probably the largest center for the manufacture of garum, a fish-based fermented condiment which was a delicacy in the ancient Roman world. Join a team of scientists as they investigate the submerged city in hopes of revealing new secrets about the rise and fall of the world's greatest empire.