In the era of Louis XIV, the famous trade port transformed into one of the biggest corsair towns. In 1995, the coincidental discovery of a shipwreck from the 18th century recalled the city once again, which had been the most prominent in the heroic epoch. Michel L'Hour, undersea archaeologist, expert of recent shipwrecks, undoubtedly has found one of the best-preserved and most promising places. The film shows how he and his team discover, step by step, under the sea and on the land, the identity and history of this ship.