Dexter's Laboratory: Ego Trip

Dexter's Laboratory: Ego Trip is an Annie Award-winning one-hour animated television special spawned from the Cartoon Network animated television series Dexter's Laboratory, produced by Hanna-Barbera (now Cartoon Network Studios) for Cartoon Network, and aired in 1999. The film features the protagonist Dexter going to the future to see his futuristic versions of himself and his eternal rival Mandark to stop the latter from taking over the world.

Ego Trip was originally intended to serve as the series finale for Dexter's Laboratory, but due to a mixed reception from critics and high viewer ratings, the series was picked up for two more seasons with the first episode, Streaky Clean, airing on November 16, 2001.

Synopsis
Robots from the future come to destroy Dexter because he saved the future. Dexter defeats them and because of hearing that he saved the future, he travels into the future to find out what it is that he did.

Plot
After routinely chasing the evil Mandark (Eddie Deezen) out of his lab when he tries to steal the "Neurotomic Protocore", Dexter (Christine Cavanaugh) is confronted with a group of robots that have appeared from his time machine. They declare that they are here to destroy the one who saved the future, and make ready to attack Dexter. Dexter easily destroys them with the use of various tools and gadgets from his lab. However, news that he is "The One Who Saved the Future" intrigues him, and he decides to travel through time to discover how cool he is.

In the first time period he visits, Dexter finds a tall, skinny, weak version of himself working in office-designing cubicles, with Executive Mandark as his rich, successful boss. The child Dexter unwittingly reveals the existence of blueprints regarding the Neurotomic Protocore from the beginning of the movie, and Executive Mandark steals it after the two Dexters move forward in time.

In the second time period, the two Dexters meet their much older self, a wizened senior citizen Dexter about the same height as the child Dexter (and Mandark as a "brain-in-a-vat", renamed as "Braindark", who can never do anything other than only complain about his situation). All the technology from the blueprints has been implemented, creating a utopian society where anything can be materialized with the power of the mind. Old Man Dexter can't remember how he saved the world, so they travel back in time to find out.

In the third time period, which appears to take place between the first and second time periods, they find a dystopic world where everyone is stupid and knowledge, science, society and technology are forbidden, controlled by Overlord Mandark, thanks to his plan about the Neurotomic Protocore. They meet Action (Hero) Dexter (Jeff Bennett), who is tall, muscular and bald (senior citizen Dexter, it turns out, wears a wig), as well as having grown a large beard and huge muscles while digging underground after Mandark stole the plans. They go back to Dexter's laboratory and build a giant robot to invade Overlord Mandark's fortress. Reaching there, they are faced by the monstrously corpulent dystopian Overlord Mandark, who has summoned versions of himself from other time periods to oppose the Dexters. A battle royale ensues, with each Dexter fighting the Mandark of his own time period.

While the Dexters struggle to prevent the Mandarks from using the core, the Dee Dee from the present timeline unknowingly is transported to hero Dexter's time and undos Overlord Mandark's dystopia by pushing a button, setting the core's flow from negative to positive. The other Mandarks are transported back to their own timelines and the dystopian Overlord Mandark is reduced to nothing but his brain, meaning that he is now Braindark, which explains about brain-in-a-vat situation from Dexter and D22's earlier encountering. After DeeDee leaves, the Dexters are upset to know that DeeDee was the one to save the future, not Dexter. In response, the Dexters build robots from the remains of Mandark's lair and orders them to destroy the one who saved the future. With the core now at a positive flow, the Dexters bid each other farewell and return to their own times.

In the present timeline, he is shocked to find that the robots he sent were destroyed by himself, the Dexter who went to the future earlier. This confuses Dexter, and he goes to eat lunch. He then glares at DeeDee when she comes up to greet him and walks away, confusing her.

Characters

 * Dexter
 * Number 12
 * Action Dexter
 * Old Man Dexter
 * Mandark
 * Executive Mandark
 * Overlord Mandark
 * Braindark
 * Dee Dee (Cameo)

Goofs/Errors

 * When Dexter kicked Mandark out of his house, the driveway is missing.
 * Dexter was underdressed piloting his Dexo-Transformer, after summoning the Robo-Dexo 2000 to crush the last robot—he's seen in his lab coat exiting it.
 * When a nude Number 12 was automatically dressed clothing by the machine, he was given a pair of black pants and a white coat, but with no signs of underwear visible underneath his pants. But when Number 12 is stripped off his clothes to be publicly spanked by Executive Mandark, he is seen in his underwear.
 * When Dexter tells his wimpy self to stop typing, Wimpy Dexter's pants turn white.