The Rick and Morty season 5 finale may have been shocking, but its central twist was actually foreshadowed in the show's first season! The irreverent Adult Swim animated series has changed a lot over the years as viewers have gradually learned more about Rick, Morty, and the rest of the Smith family. Rick and Morty finally revealed Rick's origins and backstory in the season 5 episode "Rickmurai Jack"; however, the scientist's background was only one of several ongoing plotlines concluded in the climactic finale.
The main story in Rick and Morty season 5, episode 10 followed the titular leads returning to the Citadel of Ricks, only to find themselves tangled up in a conspiracy plot by the newly elected President Morty (aka Evil Morty). This eye-patch-wearing variant of the teenage boy was first introduced in the season 1 episode "Close Rick-counters Of The Rick Kind," and the season 3 episode "Tales From The Citadel" saw the character adopt the new personal "Campaign Morty," eventually becoming "President Morty." Evil Morty has been the subject of many fan theories over the years — and the events of "Rickmurai Jack" finally provided some answers, revealing Evil Morty's true plan for the Citadel.
The finale ended with Evil Morty escaping through a yellow portal after destroying the Central Finite Curve, while the show's titular leads returned home to contemplate their next move. The finale heavily implied the Adult Swim series was undergoing a reboot: With the Citadel of Ricks destroyed and the Central Finite Curve broken — and the portal gun low on juice — it appears that Rick and Morty's dimension-hopping days may be over. What's interesting about this turn of events is that the basic premise was hinted at in the season 1 episode "Close Rick-counters Of The Rick Kind" (which also introduced Evil Morty). Rick warns Morty, "A cocky Morty can lead to some big problems, can be a real bad thing for everybody." When Morty asks him to explain, Rick dismissively responds, "I'll explain when you're older."
Since this is the same episode where Evil Morty makes his debut, Rick's words were clearly intended to foreshadow the significance of the eye-patch wearing variant, who would return to the series and disrupt the stability of the Citadel of Ricks — eventually changing the show's own multiverse structure. As Rick predicted, Evil Morty became a problem for literally "everybody" — sabotaging countless realities and variants in his quest for independence. While it's likely that the exact events in the Rick and Morty season 5 finale weren't planned until much later, this season 1 moment clearly set up Evil Morty to be a major antagonist for the show long-term. This version of Morty escaped in the end as well, which means he could return to dimension C-137 — although based on his primary motivation, that seems unlikely.
An alternative interpretation of Rick's comments in season 1, episode 10 hint at a much more cyclical view of the world. Rick's words hint at future knowledge — particularly his comment that he would "tell [Morty] when [he's] older"; while on a basic level this suggests that Rick has knowledge of the future, it's also possible that this event is part of a cycle, one that Rick has experienced previously. C-137 Rick calls himself the "Rickest Rick," and he alone played a key part in developing the Central Finite Curve — so much so, that Evil Morty needed him to complete his plan. This is one of many hints that there is something special about the C-137 Rick among the rest of the variants, and his warning to Morty implies a unique foresight into events that have yet to transpire. Perhaps he even, in some way, played a part in creating the show's multiverse in the first place. Regardless, it will be interesting to see where Rick and Morty season 6 takes the story next.