When Rick and Morty revealed its new opening theme sequence for the first time, fans were guessing as to which of the random scenes would be incorporated into actual episodes of the series. Season 4 has been a wild ride thus far, but the final episode of its first batch of five episodes has definitely taken things to the next level. Who would have guessed that the random scene of a strange robot mutant fighting off snakes would play into an actual plot in the series? Much like the other episodes this season, it ended at a completely different place than expected.
What started out as Rick getting a flat tire in space and Morty suddenly bitten by a space snake turned into Rick giving an entire planet of snakes the ability to time travel -- eventually leading to a full out robot apocalypse straight out of The Terminator.
When the snake that bites Morty dies, Rick reveals that it's a lone female snake that was sent into space as part of a natural evolutionary cycle of technology. Feeling terrible about it, Morty catches another snake on Earth and sends it into space. It's soon revealed that the first snake comes from an entire advanced society of snakes (who listen to "Snake Jazz") that grow to learn more about their mysterious new visitor.
Breeding together with this Earth snake shakes up the evolutionary chain on this snake planet and soon Morty finds himself attacked by time traveling robotic snakes (a la Terminator) sent back in time to kill him from saving the organic snake society. In typical Rick and Morty fashion, this evolved to the point where a small android (as seen in the Season 4 opening) comes back in time to protect Morty -- only to be hilariously killed by Beth.
Soon after, Rick and Morty head to the snake planet and find that it's been overrun by T-800 like snakes and other time traveling assassins. So the only way to fix it is to give them time travel by doing the math himself, and thus Rick closes the loop on this Snake Terminator society in a series of increasingly odd events that not only parody Terminator, but pay homage to other time travel flicks like Back to the Future.
Speaking of Back to the Future, star of the film Christopher Lloyd has actually gone on record about his desire for a fun crossover with Rick and Morty. Speaking at German Comic Con Dortmund, Lloyd complimented the series and even thought about how a crossover could happen, "I think it's fabulous. I've watched it, I love the humor in it, I love the characters. I've had a fantasy that they make another Back to the Future, Back to the Future 4. And Back to the Future 4 — it's not happening — but if it did, Back to the Future 4 collides with Rick and Morty. Someway, somewhere in another time zone, in another space zone."
The final five episodes of Rick and Morty Season 4 will return sometime next year.