The Laughing is the second part of the 23rd episode in Season 2 of Dexter's Laboratory, which first aired on January 21, 1998. In this episode, Dexter gets bitten by a pair of clown dentures during Dee Dee's birthday party, causing him to turn into a mad clown nightly and terrorize the town with his antics. This forces Dee Dee, who takes mime lessons, to stop him.
The episode begins as Dee Dee bikes up to her house talking about why she has to go do things on her birthday. Then she goes to the fence door and everyone jumped up and yelled "Surprise!". Then Dee Dee realized that everyone threw a surprise party for her. When they were eating cake, Mom announced that a clown is here. Then he starts goofing around, and then he tells an old joke. ("Why is 6 afraid of 7?". "Cause 7 ate 9!") Everyone laughs except Dexter who didn't get the joke. But then the clown trips on a rock and then his dentures shoot right out of his mouth and then they sink deeply into Dexter's arm. Then the clown apologizes for what happed, later, the family was having dinner. Then Dee Dee repeated the old joke, then Mom and Dad laughed, and then Dexter laughed in a funny way. Then he goes up to his room and then transforms into a Were-Clown.
Then he goes into the city and creates chaos, and he even stopped a date between a French-accented man and woman. The next day, Dexter wakes up and sees that Dee Dee is in his room and that his room his covered with balloons. Then Dee Dee tells Dexter that he doesn't remember what happened, and then she shows him a newspaper headline which it says "Crazy Clown lose in town". Then Dexter reads the newspaper, but he doesn't recognize that the clown is himself. Then Dee Dee tries to prove it to Dexter that he's the clown, by taking a tracing paper on the clown picture, and then drawing Dexter's picture on it, but he has already gone into his lab and then he makes an antidote for his arm, but it isn't ready yet.
Then he watches two robots bump into each other, and then he starts laughing uncontrollably and turning into the Were-Clown again. Then he goes out and then he causes a traffic jam and then lots of cars crash. Then a policeman said that he needs backup. Then Dee Dee goes to a mime school where everything is completely quiet, then she yells out for help and then all of the mimes cover their ears. Then a mime teaches her how to witness the power of mimes. When they were done, the mimes give Dee Dee a uniform with the completion of her mime training, and then she lets out a loud thank you, then the mimes covered their ears again. Outside, Dexter is in a rambunctious chase with policemen and a dog. Out of nowhere, Dee Dee shows up, dressed as a mime, captures Dexter, and she takes him to his lab and then she cured him. Despite Dee Dee saving the day, Dexter's ungrateful ego tells her that he would have saved himself eventually without her help. Then Dee Dee traps her ungrateful brother in a mime box.