Clink! Clankety-bang! Thump-whirr! That's the sound of Papa at work. Although he is an inventor, he has never made anything that works perfectly, and that's because he hasn't yet found a truly fantastic idea. But when he takes his family fishing on Lake Michigan, his daughter Virena asks, "Have you ever wondered what it's like to be a fish?" -- and Papa is off to his workshop. With a lot of persistence and a little bit of help, Papa -- who is based on the real-life inventor Lodner Phillips -- creates a submarine that can take his family for a trip to the bottom of Lake Michigan.