Players take the part of captains of cargo ships transporting merchandise over the North Sea during WWII. The board is perforated and placed over an undulated plastic landscape so that certain areas become shallow. For each of the four different orientations of the board there is a map depicting the shallow areas. Two patrol boats move randomly around the board and the players try to avoid them. Each transport is worth money and points, the first player to reach 25 points and 300.000 Swedish crowns is the winner.