The Rats

"Rats, we're rats, we're the rats. We prey at night, we stalk at night. We're the rats."

The Rats are a rag-tag group of rebels, doing what they want, when they want. They are led by a Giant Rat, who "makes all of the rules." In Timeline A, they busy themselves with trying to steal the Mayan Treasure from the Diner in Simple City, as part of the course of events leading to the spontaneous destruction of planet Earth. In Timeline B, however, their leader, Giant Rat #9,375, decides to go to Michael's birthday party instead, becoming entangled in the controversy surrounding the Noah's Ark Toothbrush in the process. It is possible that the Rats have attained celebrity status in Simple City, as they produce music which Michael dances to at his birthday party.

Timeline A
In Timeline A, the main focus of the Rats is to steal the Mayan Treasure. They hang around outside Dastardly Manor and follow the Thieves to Simple City. They then enter the cave where the Treasure is held, and then killing the Thieves' leader, Dick Dastardly, as well as Gerard the Guardian. During the fight, a single casualty is suffered on the Rats' side as Giant Rat #9,375 is killed. This is no issue for the Rats, however, as their leader is immediately replaced by Giant Rat #9,376 (see System of ascension). The Rats succeed in taking the Mayan Treasure for a moment, even eluding the Police, but are eventually caught and brought to an untimely end by the Cat Police, just before the end of the world.

Timeline B
Because the Mayan Treasure belongs to the Cats in Timeline B, the Rats instead decide to attend the birthday party of Michael. On the way, Giant Rat #9,375 becomes stuck in the toilet. Seizing his opportunity, his second in command flushes the toilet, drowning the Giant Rat. He is then promoted to Giant Rat #9,376. At the party, the Rats leave behind their present (a small Rat in a box that is Michael's "new best friend") and leave. They take the corpse of the clown with them, saying "Thanks for the guy." The clown's body doesn't fit down the toilet, much to the Rats' dismay. At this moment, the Cat Person pauses the recording and asks the Rats for their opinions. This is when it is revealed that the entire video up to this point has been filming for a fictional movie that the Rats star in. The Cat Person is very busy explaining that the movie must sell toys, audio casettes and the like when the Dogs launch a MIDTD "Fat Guy" into the building to recruit the assistance of the Rats. Two of the rats leave, however, and only Giant Rat #9,376 is teleported to the Dog Capital. Here, he is introduced to the Noah's Ark Toothbrush when the Cat Person reveals his identity, exclaiming "The infiltration was a success!" In the resulting crossfire, the Giant Rat takes the Toothbrush and uses it to brush his teeth, claiming that "''That's a pretty good toothbrush." ''He then flushes the Toothbrush down the toilet. The Giant Rat can then be seen again when he and Gerard attempt to thwart the plans of the Cats. Gerard fights off the fierce Cat Golem and orders the Giant Rat to throw the Toothbrush into the fires of Mount Doom. The Giant Rat finds the next best thing - another toilet. He flushes the Toothbrush down the toilet, proclaiming, "Mount Doom." This is the last known event of Timeline B, despite the non-existence of a cataclysmic event like the one that ended Timeline A. It can only be presumed that the Rats lead a normal life after this.

System of ascension
In both Rat Movies, the system of ascension can be seen in action. As one Giant Rat is killed, his second in command immediately swells to a size that can only be described as "giant", becoming the new leader of the Rats. This is how both Giant Rats #9,376 come to power. The exact process by which a rat becomes Giant is unknown and has yet to be explained by science. The high number of Giant Rats can therefore be blamed on the fragility and recklessness of the Rats that so often leads to their tragic end.