Based in part on an original sketch devised by Graham Chapman and written by Chapman and Adams for the Graham Chapman Television Show “Out of the Trees,” 1975.
From The Utterly Utterly Merry Comic Relief Christmas Book, 1986.

Young Zaphod Plays It Safe

A large flying craft moved swiftly across the surface of an astoundingly beautiful sea. From midmorning onward it plied back and forth in great, widening arcs, and at last attracted the attention of the local islanders, a peaceful, seafood-loving people who gathered on the beach and squinted up into the blinding sun, trying to see what was there.

Any sophisticated, knowledgable person who had knocked about, seen a few things, would probably have remarked on how much the craft looked like a filing cabinet—a large and recently burgled filing cabinet lying on its back with its drawers in the air and flying. The islanders, whose experience was of a different kind, were instead struck by how little it looked like a lobster.

They chattered excitedly about its total lack of claws, its stiff, unbendy back, and the fact that it seemed to experience the greatest difficulty staying on the ground. This last feature seemed particularly funny to them. They jumped up and down on the spot a lot to demonstrate to the stupid thing that they themselves found staying on the ground the easiest thing in the world. But soon this entertainment began to pall for them. After all, since it was perfectly clear to them that the thing was not a lobster, and since their world was blessed with an abundance of things that were lobsters (a good half a dozen of which were now marching succulently up the beach towards them), they saw no reason to waste any more time on the thing, but decided instead to adjourn immediately for a late lobster lunch.

At that exact moment the craft stopped suddenly in midair, then upended itself and plunged headlong into the ocean with a great crash of spray that sent the islanders shouting into the trees. When they reemerged, nervously, a few minutes later, all they were able to see was a smoothly scarred circle of water and a few gulping bubbles.

That’s odd, they said to each other between mouthfuls of the best lobster to be had anywhere in the Western Galaxy, that’s the second time that’s happened in a year.

The craft that wasn’t a lobster dived directly to a depth of two hundred feet, and hung there in the heavy blueness, while vast masses of water swayed about it. High above, where the water was magically clear, a brilliant formation of fish flashed away. Below, where the light had difficulty reaching, the colour of the water sank to a dark and savage blue.