Rick and Morty co-creator Justin Roiland isn't afraid to go away from the script and Rick's "Wubba Lubba dub-dub" catchphrase is a result of his improv. The animated series on Cartoon Network has made quite a name for itself since it debuted in 2013. Through three seasons, Rick and Morty has routinely drawn praise for the smart and unique comedy that comes from its writing.
As a result, the series' lead characters of Rick Sanchez and Morty Smith have become complex and fascinating characters to explore. While the series primarily focuses on one particular pairing of Rick and Morty from the C-137 universe, its ties to the multiverse have allowed the show to highlight other sides of Rick and Morty too. As the series approaches its fourth season, Rick and Morty have well-defined personalities, traits, and - in Rick's case - even a few catchphrases. But one of his more popular ones wasn't originally part of the series.
Rick's "Wubba Lubba dub-dub" catchphrase was introduced in the first season of Rick and Morty, and has been a phrase he has said many times since. But, as discussed in the Screen Rant video featured at the top of this post, the unusual saying is one of many things that were not in the scripts for the series. Instead, Roiland came up with "Wubba Lubba dub-dub" while in the booth recording Rick's lines, making this one of the best showcases of improv that Rick and Morty has to offer. Roiland and Rick have expressed that inspiration for the phrase came from Arsenio Hall's catchphrase that he did on his show.
When Rick first started using the catchphrase, he would do so to express that he is happy or after he made a joke. It was just an additional bit of comedy for Rick and Morty to use... until it became something else. This isn't referring to fans using the catchphrase on their own terms, but rather how later episodes revealed a more troubling truth behind the phrase. When Birdperson hears Rick say this phrase, he tells Morty that in his language "Wubba Lubba dub-dub" means "I am in great pain, please help me."
Even though this translation for "Wubba Lubba dub-dub" isn't quite as fun as it is to say the phrase, Roiland's ability to come up with it on the spot does highlight part of the magic behind Rick and Morty. While it is for the best to have the general story for a TV show or movie planned, allowing lines or moments like these to change on a whim can turn out for the better. We don't know what the original catchphrase for Rick was in the moment, but its difficult to believe something better than "Wubba Lubba dub-dub" was part of Rick and Morty's scripts.