Doug's Worst Nightmare is the second part of the fifth episode of the second season of Nickelodeon's Doug.
When Roger starts acting nice, Doug's worst nightmare becomes a reality - Roger has developed a crush on Judy. The only thing that can make things worst for Doug is if Judy has fallen for Roger.
Doug is trying to stop Roger, who appears to be lovesick, from running, but to no avail. Judy also comes around and attempts to kiss him, but only end up kissing Doug, who is between him, on each side of his head after wiping their mouths in disgust. Doug screams in terror as he discovers that Roger is in love with his sister.
Doug and Skeeter are watching a movie about a monster beet destroying the town when Judy changes the channel to her show Shakespeare on Ice, much to the boys' annoyance. So Skeeter suggests that he and Doug can watch the remainder of the movie at his house instead, only to find that Roger is at the front door. Doug asks what Roger is doing at his home, to which Skeeter replies that he maybe wants to cream him, not needing a reason for doing so. Roger comes in and calls Doug and Skeeter his "buddies," confusing the two. Skeeter discovers that Roger has on cologne and Doug notices him making a lovesick face while looking straight towards the living room. To Doug's horror, he realizes that Roger has a crush on Judy. Skeeter ask Doug if he could imagine Roger hanging around his house.
Doug's imagination: Doug is sitting at the table along with Judy and Roger, the latter wearing a beret and a pair of shades. When Doug asks for either of the two to pass the banana pudding, Roger serves him it by throwing it in his face as he and Judy laugh.
When Skeeter tells Doug that Roger doesn't seem like the Judy type to him, Doug has an idea and lets Roger know that Derrick Derrickson, the guy wearing a dress ice skating on television, is Judy's celebrity crush and that she only goes for guys who are more high class and sophisticated.
This, however, only prompts Roger to change his image as the next day in school, he is dressed the way Derrick Derrickson was dressed in the Shakespeare on Ice show and is even talking in Shakespeare's jargon. During lunch, Roger's gang invite Doug over to the boys' restroom and show him Roger reading from the book of Shakespeare's Greatest Hits. When Roger notices them watching him, demands his gang to leave and talks to Doug in private, telling him that he is desperate to get Judy's attention. Doug tries to convince Roger that Judy isn't right for him, but to no avail. Doug then realizes that Roger has gone insane.
During the evening, Roger uses a ladder to climb up Judy's window to greet her, only to find out that it is really the Dinks' bedroom window and that Tippy reminds him that he is thirty years too late. Roger is startled in surprise and tumbles down onto a bush. Doug comes outside and tells Roger that Judy is at rehearsal. Roger then offers a note to Doug to give to Judy. Doug wonders if he should give his sister the note.
Doug's imagination: Doug is seen on a ship in the middle of the ocean dressed as a hunter, wondering if he should deliver the letter to Judy.
When Doug gives the note to Judy when she returns home, she opens it and reads the poem inside (which Roger took from a play), as well as reading Roger's name on it. She then attempts to meet Roger at the Honker Burger. Doug and Porkchop chase after her to stop her, only to discover that they are too late. When Judy meets Roger, she acts as the typical dramatic actress and walks away. Roger later loses interest in her when he realizes that she is even weirder than Doug himself. His gang later shows up dressed as Derrick Derrickson was in the TV show. Roger tells them that they are lucky to have him as their leader and takes them with him to leave as Doug and Porkchop start laughing as the episode ends.