Donald's sneezes at an auction are mistaken for bids on a houseboat and soon he and the nephews are sailing down the Ohio River. There they encounter a huge serpent, which they later learn is an elaborate submarine whose captain gets his pleasure from scaring people.; Donald falls on his head when getting up one morning and turns into a pyromaniac, setting harmless fires but also getting the blame for big fires set by another firebug.; The nephews play ball at the beach with a baby seal, and this sets Donald to dreaming of how much money he could make with a trained seal act.