The Vat of Acid Episode.While on a mission, Rick and Morty trade special gems with alien gangsters. The gangsters betray them and Rick fakes his and Morty's deaths by jumping into a vat of fake acid. However, as they hide in the vat, the gangsters don't immediately leave. Morty grows impatient and kills the gangsters with Rick's gun, accusing Rick of having a bad idea with the vat of acid. Morty then dares Rick to invent something based on one of his ideas, where he can create a "save point" in time that he can return to in order to escape death or correct mistakes. Rick grudgingly agrees creating a special remote, but Morty takes it before he can explain how it works. Morty then commits numerous crimes and pranks and resets himself to avoid consequences. Eventually, though, Morty falls in love and starts a relationship with a young woman. When they end up stranded in the wilderness, Morty considers using the remote but calls for rescue instead, wanting to preserve the relationship he has. However, after Morty is rescued, Jerry accidentally presses the remote, resetting Morty back to before the relationship started. Morty fails his attempt to restart the relationship when his save point is accidentally overwritten, and he returns to Rick, saying he has learned his lesson that one shouldn't live a consequence free life. Rick then reveals that the remote does not reset the timeline, but instead teleports Morty to an alternate dimension, and also kills the Morty native to that dimension so Morty can take his place. Horrified, Morty begs Rick to undo everything, so Rick merges all of the alternate dimensions. While this prevents the deaths of the alternate Mortys, everybody remembers the crimes Morty committed, and the only way he can escape is to jump into a vat of fake acid to fake his death. Satisfied his point was proven, Rick reveals they were in an alternate dimension this entire time, as he didn't want to risk Morty ruining their home dimension.