Martin XIII.: The oceans seem to be the Nehls' second home. But there is one exception that Grandpa Nehl, alias Martin XI, captain of a training sailing ship, is not at all happy with. His son Martin XII is the first of the family to work ashore. A scandal, really, but Grandpa Nehl doesn't give up. He hopes that his grandson Martin XIII will carry on the maritime tradition. But behind his grandfather's back, he also goes his own way. And so a huge row is brewing, if it weren't for twin sister Martina.