Drakken and Shego attempt to breach Area 51 with Commodore Puddles (having become a giant) while Ron uses the attack to shoot his monster movie.
Ron tries to film his own monster movie in his garage, starring Rufus as the monster, but Rufus breaks character by snacking in the middle of a shot. Kim thinks Ron is taking the film too seriously, then stumbles upon a home video labeled "Ron's Big Day". Ron quickly snatches the video from her, and explains that he is determined to redefine the monster movie genre at the upcoming Tri-City Film Festival. Wade calls in and says Dr. Drakken has ordered a shrink ray, which is being shipped to the Mohave Desert.
In his desert lair, Drakken reveals his plan to Shego: to shrink himself to microscopic size, so that he will be able to sneak into Area 51. While they are setting up the shrink ray, Drakken's poodle, Commodore Puddles, wants to be let out. Drakken tells him to wait, and Shego reminds Drakken that he agreed to take care of the dog if he was allowed to have one. Drakken insists that he will, but later, leaving Commodore Puddles disappointed.
Kim and Ron get ride to the desert from Special Agents Smith and Smith, then travel toward Drakken's lair with rocket skates and a skateboard.
Just as Drakken is about to shrink himself, Commodore Puddles distracts him again, which gives Kim and Ron time to burst in. Shego attacks Kim, and Ron begins filming the action for his movie. Out of patience, Commodore Puddles relieves himself on the shrink ray, which causes it to begin sparking. Kim accidentally tosses Shego into Ron, and the resulting collision knocks Rufus and Commodore Puddles onto the shrink ray's targeting platform. Commodore Puddles shoves Rufus into the shrink ray, which targets the dog. Shego then knocks Kim into the ON button, and Commodore Puddles is hit by the ray's beam. However, instead of shrinking, the dog begins growing, until his head bursts through the roof of the lair. Drakken and Shego climb on, now planning to just invade Area 51 with the now giant Commodore Puddles.
The approach of Commodore Puddles terrifies the residents of a nearby trailer park.
Kim is concerned about stopping the dog, but Ron is more worried that his film is incomplete. Kim and Ron rush ahead to Area 51, where she tries to explain the incoming threat to the guards. Commodore Puddles arrives while they are talking, so the base shifts into battle stations, and Kim is directed to General Sims, who surprisingly has protocol in place to deal with attack by a giant dog. Jets drop giant doggie treats as a distraction, but Commodore Puddles spits out the first and ignores the rest, apparently accustomed to better treats. Next, giant dog whistles are deployed, in the hopes of forcing Commodore Puddles into a large pet carrier. The soldier with the remote is knocked down, forcing Kim to retrieve and activate the remote. This works a little too well, because while Commodore Puddles begins to retreat, several normal-sized dogs show up in a frenzy and knock over the whistles.
The soldiers, along with Kim and Ron, retreat to the underground levels of Area 51. On the way, Kim asks what the big secret of Area 51 is. Oddly enough, General Sims reveals that all the rumors that people hear about Area 51 are true, because the base is careful to only leak information that is entirely accurate, although no one outside knows this. Commodore Puddles begins to dig his way into the base. Out of options, General Sims prepares to start the base's self-destruct sequence in order to keep it out of Drakken's hands. However, he agrees to give Kim ten more minutes to stop Drakken at her request.
Kim manages to trip Commodore Puddles by tying up his legs, but Drakken simply has him roll over to get free. Commodore Puddles captures Kim and Ron, but Rufus escapes in one of Kim's rocket skates.
As Drakken begins to celebrate his victory, Rufus returns, now giant-sized as well. While Rufus and Commodore Puddles begin fighting, Kim gets free and starts fighting Shego. Both Commodore Puddles and Shego are defeated and locked in the pet carrier. Drakken sneaks onto an alien spaceship and takes off, only to discover three aliens on board who seem unhappy that he tried to steal their ship.
At the Tri-City Film Festival, Ron thinks his film is sure to win. However, Kim hears the audience laughing during the screening. Special Agents Smith and Smith show up and inform them that they switched tapes, since all of the footage Ron captured was deemed classified. Unfortunately for Ron, the tape they substituted his movie with was "Ron's Big Day", a home video of Ron learning to use the toilet.
- 19th episode in chronological order.
- Drakken and Shego first planned to use a shrinking ray, but the outcome was a giant poodle instead.
- When Rufus and Commodore Puddles are fighting the second time, Rufus uses the same trick that Commodore Puddles used earlier, but with a wrestling move.
- The alien flying saucer is the same design as the C-57D Cruiser from Forbidden Planet, but smaller.
- In this episode, Commodore Puddles was pink, but in Kimitation Nation, he was white. Although not chronicled, such dying is fairly routine for poodles.
- Commodore Puddles was introduced in Kimitation Nation.
- Kim Possible: The Complete Second Season