"Big Bots" is the first part of the 34th episode of season 2 in Dexter's Laboratory, which first aired on April 8, 1998. In this episode, Dexter and Dee Dee must save an island from an erupting volcano, but fail to do so because of their constant arguing.
Dee Dee is in the front yard playing with her Ponypuff Princess, and is suddenly stopped by giant footsteps. She watches as Dexter pilots the Robo-Dexo 2000 toward the house. Upon arrival, Dexter explains his battle with a monster while acting out what happened. Dee Dee gets inspired and wants a giant robot of her own. At first, Dexter laughs at her, but soon builds her one. Dee Dee watches as her brother builds her robot, much to her excitement. She is happy at first, but Dexter tells her it's just a display and goes to dismantle it. Suddenly, the alarm goes off and Computer shows Dexter and Dee Dee the emergency. They both go suit up, get in their giant robots, and Dexter flies off to the volcanic island. He greets the villagers, but sees that Dee Dee has arrived at the same time. A fight between Dexter and Dee Dee starts breaking out, whereas the volcano starts erupting. Dexter goes to pick up a giant rock to stick in the volcano, and turns around to see Dee Dee putting the villagers in the shark-infested water. Dee Dee sees the sharks and runs over to her little brother and lands on top of the rock.
Dexter then flings Dee Dee to the other side of the island where the villagers are washed back onto the shore. Dee Dee alerts Dexter about the rock above his robot and destroys it with her finger laser. Dexter gets infuriated and scolds Dee Dee, which she retaliates by using Dexter's "big mouth" to plug the volcano. Another fight breaks out between them, with Dexter vigorously shaking Dee Dee's robot. She counterattacks by firing an energy beam at him. Dexter jumps out of the water and fires lasers at Dee Dee, which she blocks by making a shield. They both jump at each other and use melee attacks. The villagers all run in fear as the volcano is seconds away from erupting. Dexter and Dee Dee both stop fighting and head for the volcano's mouth. The villagers stop running in terror, and laugh as Dexter and Dee Dee sit on the volcano, much to their humiliation.