When his family is suffering from the flu, Dexter tries his best to not acquire the illness, but his efforts are thwarted by a sick Dee Dee’s presence in his lab.
While out for dinner at a pizza restaurant, Dexter tries to slow down the “Whack the Weasel” machine to win a stuffed Monkey doll before Dee Dee does. Security captures him for tampering with the machine, and he falls into the hands of a mad scientist.
Dexter creates a satellite to clean stains off of his clothes, but it goes horribly wrong when Mir space station hits the satellite that Dexter created and the satellite becomes damaged, causing the fabric beneath each stain to be eliminated as well.
When Dee Dee frees one of Dexter’s robots by removing the wrench that froze it, the robot tries to destroy anyone who is mean to Dee Dee, including her friends, her mother and Dexter himself.
Dexter and Mandark bring the Abraham Lincoln and George Washington faces respectively on Mount Rushmore to life and make them fight each other to determine who is the best.
When his television show is interrupted by the Emergency Broadcast System, Dexter sets about fixing any emergencies in the neighborhood to make the signal go away.
Dexter travels to Mars to find intelligent life, unaware that Dee Dee has stowed away in his space capsule. After Dee Dee gets covered in red dirt, Dexter thinks she is a real-life Martian.
Dexter and Dee Dee’s secret decoder rings hold the keys to joining the Action Hanks and Pony Puff fan clubs respectively, but they interchange the clues by mistake, causing them to switch clubs.
When his mother falls ill, Dexter creates a robot to do her chores. Dee Dee gets hold of its remote control and wreaks havoc, forcing Dexter to create a second robot to counter Dee Dee’s.
Dexter’s lab is threatened with repossession unless he can repay his debt to NASA. When Dee Dee wins the same amount in a lottery, he decides to steal her money out of desperation.
Dexter finds a lost Labrador Retriever, but when he teaches the dog to speak human language, he turns out to be very annoying, prompting Dexter to find the dog’s owner.
