In 2006, numerous archaeological finds were made in the Tollense valley in Western Pomerania that point to the first known multi-ethnic battle in Europe, dating back to around 1250 BC. An unprecedented number of skulls pierced with arrowheads and broken bones from various ethnic groups were discovered. The level of brutality shed new light on the concept of a war of attrition. Since then, a veritable gold rush has broken out in the region, particularly among amateur divers. "What's in our bones?" takes a dive into the adventurous world of underwater archaeology.