Beaver is suffering from a toothache. June manages to get him a last minute appointment with their dentist, Dr. Harrison, who, after taking some X-rays, will let them know later that day if there is anything of issue with the tooth beyond a probable cavity. Beaver isn't too concerned, as he likes the trips to the dentist if only to get the little toy army men they give away and the special feeling he gets from sitting in the big chair. But Beaver's feelings change after Lumpy tells Beaver, who has never had a cavity before, that they will drill a big hole in his tooth. Lumpy's story is that the bigger the hole, the more money the dentist will make, hence the likelihood that the hole will be huge. Beaver does whatever he can to get out of going back to the dentist. But not disappointing his parents, who are trying to get him from being afraid, may be the harder task in his mind.
—Huggo