Doug's Dental Disaster is the second part of the twelfth episode of the second season of Nickelodeon's Doug.
Doug's tooth hurts when he gets a cavity after biting into a candy bar at the movies, and afterwards has to go to his dentist. Although he doesn't want to go to the appointment, he daydreams how Secret Agent Smash Adams would handle a dental situation, but soon his frown turns to a smile when he meets his new female dentist, Dr. Kay.
The episode starts off with Smash Adams tiptoeing through the house and encountering a fireplace. He uses a secret switch, which activates the wall, causing it to rotate by virtue of a secret switch. Smash enters a mysterious cave and presses a green button under a television screen, revealing villain Dr. Decay. The villain activates a trap door, which Smash Adams is standing under. The secret agent falls through the trap door and lands on the dental chair, which he is strapped in. It is revealed that it is a movie Doug and Skeeter are watching at the movie theater. Doug bites into his chocolate bar and gets a toothache. When he runs into the bathroom to take a look at it through the mirror, he discovers that he has a sore tooth.
The next scene later switches to Doug portrayed as Smash Adams. He tiptoes through the house and then comes to a fireplace. It turned around by virtue of a secret switch and Doug comes face to face with some bad guys. As he fights off his foes, one of the villains poke his jaw and the scene shifts back to reality, showing Doug holding onto his jaw.
At the Honker Burger, Skeeter takes a look of Doug's teeth and tells Doug that he has a cavity. When his friends tell him that he would have to go to a dentist to get it filled, Doug explains that the dentist "give him the willies." Patti tries to convince him that it won't be bad. But when Doug asks her how many cavities she had, she says that she hasn't had one yet and would be scared of the drilling and the needles, demoralizing Doug. Roger comes around and makes Doug feel apprehensive by indoctrinating the painful procedures that he will receive once he goes to the dentist for an appointment.
As he gets ready for bed back at home, Doug thinks about what Roger told him and tells himself that dentists won't just let anybody in and pull their teeth.
Doug's imagination: In Dr. Decay's room Smash Adams, portrayed by Doug, is sitting on the dental chair getting his teeth checked by the villain. Smash reminds him that he will never make him talk. Dr. Decay, however, would much rather have him suffer instead and holds a powerful drill to use on Smash's mouth.
While Doug sits on his front porch, he decides to make the pain dissipate on its own. But when he asks Mr. Dink if he had a cavity before, Mr. Dink informs him that he had so many cavities that he lost all of his teeth and had them replaced with titanium steel dentures. Cognizant of how ignoring his cavity would cause impending risks, Doug becomes encouraged to circumvent the same fate by going to the dentist to fill up his sore tooth.
At the dentist, Doug waits in the waiting room and reads a framed college diploma of Dr. Kay on the wall and realizes that maybe the dentist won't be bad after all. He is then guided to the hallway by a dental assistant and becomes a bit apprehensive when he hears a patience screaming. Doug states in his head that he never expected it to be as bad as it would turn out and that even Smash Adams would think twice about it.
Doug's imagination: Smash is standing by Dr. Decay, who is about to drill his mouth. Smash breaks the drill with a kick, hops on top of a chandelier, and leaps out the window. He lands inside his car and drives away.
When Doug is guided inside Dr. Kay's dental room, he relaxes in a dental chair to wait for the dentist. Doug feels nervous as he takes a look around the room and the dentist arrives, revealed to be a female dentist named Dr. Kay. The dentist prepares to fill up his tooth as Doug waits for the procedure.
After Dr. Kay finishes, Doug feels great, saying that it wasn't that bad. Dr. Kay tells Doug that he is his best patient due to how calm he was in comparison to the other patients that go to the dentist. Just then, Roger emerges inside the room in fear, hiding for Dr. Kay, despite the fact that she is only going to clean his teeth. He dashes out of the room and runs away screaming. Doug states that Roger has a "super-low threshold of pain" and he and Dr. Kay start laughing.
The next scene shows Doug writing in his journal about his experience at the dentist. He then looks out the window to discover that Mr. Dink is looking for his dentures through the yard. Porkchop then shows up in a flamenco outfit, using the dentures as castanets as the episode ends.
- While Doug was in the waiting room, a slow down version of Killer Tofu was playing in the background.