A boy works on his older brother's pleasure yacht that ferries rich people across the Thames River. One fall day, he finds a pregnant red fish that appears to be in hibernation so he keeps it in an ice chest. When spring comes, the fish has become transparent except for the spawn that remains red. The boy takes the curious fish to an old scientist at Cambridge who says, "Sorry old chap, but we'll have to perform a dissection on this one." The boy looks at his watch and wonders how he's going to get the fish back because his brother wants to use it as a display.
