A team dive down through the frigid depths of the Gulf of Finland, the easternmost section of the Baltic Sea. They’re heading for a shipwreck they believe probably dates from WWI or WWII. Yet that’s not what they find. Instead they come across something entirely unexpected. It’s a merchantman which sank some four centuries ago. But what utterly astonishes the Finnish divers is the fact that the 400-year-old wooden ship is almost entirely intact.