Dimension C-137 is the universe where the mainstream Rick and Morty are often identified as coming from. Given that Rick qualified his current Jerry as not being from the same universe as him, viewers are to understand that this dimension was overrun by Cronenbergs in "Rick Potion #9."
Biography[]
Dimension C-137 first appeared in the Pilot episode and appeared in every episode since then until "Rick Potion #9", wherein it made its last appearance. In this episode, Rick makes a love potion for Morty to use on Jessica. However, the side affects of the potion would go out of control if that person has the flu (unless that person is blood related to them), and flu season was happening at that very moment, which quickly spread to everyone in the world, making them all madly in love with Morty. Rick used an antidote on them, but this only turned them into a bunch of hideous, disgusting monsters known as Cronenbergs and so everyone in the world (except for Beth, Jerry, and Summer) was infected with the Cronenberg virus. Rick didn't bother trying to make a potion to cure them, and so he just traveled to an alternate reality where he did put in the effort into saving them and resetting their dimension to normal again. Here, this dimension's version of Rick and Morty died, with Rick and Morty taking their places without anyone noticing. Meanwhile, alternate versions of them from another dimension where everyone is born a Cronenberg, named Cronenberg Rick and Cronenberg Morty, did the exact same thing in their dimension and turned everyone into normal humans. They left their own dimension and entered Dimension C-137, where every normal human was transformed into people that matched the people in their dimensions, perfectly.
As of now, Dimension C-137 is completely overrun by the Cronenberg race and the only three humans alive are Beth, Jerry, and Summer who are living out the rest of their lives happily in a post-apocalyptic world, in a burned down house. Beth and Jerry are now happy with each other in their relationship and no longer argue, and take turns with Summer acting out movies and TV from memory to make up for their lack of entertainment. At the end of "Rick Potion #9," Summer can be seen acting out a scene from "Jaws."[1] Beth also mentions that she has finally achieved true happiness now that Rick and Morty are no longer with her. The Cronenberg race and the rest of the Smith family are apparently far apart enough, that they never interact with each other, for unknown reasons, so both races don't need to worry about each other and the Cronenberg versions of Rick and Morty never have to interact with the real Smith family.
Dimension C-137 would be mentioned again in the episode Rixty Minutes, when Morty showed Summer the tombstones in the backyard where Rick and Morty were buried, telling her the whole story of Rick Potion #9. It was also mentioned again in Close Rick-Counters of the Rick Kind, by the Council of Ricks and it was also briefly seen in a screen, showing Rick's memories. One of them was him putting the helmet on Snuffles from the episode Lawnmower Dog, Rick holding Morty when he was a baby, and another one was of Rick giving the love potion to Morty from Rick Potion #9. There were also scenes of Rick and Morty flying in the space cruiser, and one of Rick, lying down on the floor, and Morty passing him his canister, but it is unknown if those took place in the old or new dimension. In the episode Total Rickall, there was a flashback montage to all the funny catch phrases that Rick has used. One of which was one he was using, while playing cards with Snuffles. This had to have been Dimension C-137, because Snuffles left the family in the episode Lawnmower Dog, which was before events of the dimension transition in the episode Rick Potion #9. There were very many other flashbacks of moments in time that actually happened, but none of them proved that they were in Dimension C-137.
The most recent mention of Dimension C-137 is in the episode Mortynight Run, when Rick is asked to identify his home dimension for identification purposes when returning to pick up his Jerry. Because Jerry is not from Rick or Morty's home dimension of C-137, Rick marks him as "N/A."