Peterson, a crew member of a spaceship visiting Mars buys an enormous pig-like creature known as a "wub" from a native just before departure. Franco, his captain, is worried about the extra weight, but seems more concerned about its taste. However, after takeoff, the crew realizes that the wub is a very intelligent creature, capable of telepathy and maybe even mind control. Peterson and the wub spend time discussing mythological figures and the travels of Odysseus. Captain Franco, paranoid after an earlier confrontation with the Wub which left him paralyzed, bursts in and insists on killing and eating the wub. The crew becomes very much opposed to killing the sensitive creature after it makes a plea for understanding, but Franco still makes a meal out of him. At the dinner table, Captain Franco apologises for the "interruption" and resumes the earlier conversation Peterson had been having with the Wub - which has possessed the Captain's body.