10. Auto Erotic Assimilation
There are many standout moments within the Rick and Morty series that help to see the show as something more than a silly Back to the Future parody cartoon series. It doesn't always merely deal with fun sci-fi scenarios, but some more complex ideas that leave a significant impact on the characters involved in the show.
In this episode, we see how Rick operates when in a relationship. This relationship is with an alien presence known as Unity, who assimilates beings into a large scale hive mind, but this seems fitting for Rick as the dramatic flare of the relationship connects with his somewhat unfathomable existence.
However, towards the end of the episode - after taking Unity for granted and making them spiral into the same self-destructive habits he delivers upon himself - they leave Rick, and the only remains he finds is a note dictating why this has happened.
The letter is heartbreaking but also accurate, and in a rare moment within the series, we see how Rick's response to heartbreak reveals the deeper levels of self-loathing and destructive personality his otherwise confident persona hides.
Alongside this excellent character work, we also follow Beth and Jerry in a fun side story surrounding a murderous creature known as Blim Blam, which helps to juxtapose the severity of the episode nicely.
Overall this is a great, fun episode that peels back the curtain a little on Rick Sanchez.