SEINFELD -- Season 9 -- Pictured: (l-r) Michael Richards as Cosmo Kramer, Jason Alexander as George Costanza, Julia Louis-Dreyfus as Elaine Benes, Jerry Seinfeld as Jerry Seinfeld (Photo by Andrew Eccles/NBC/NBCU Photo Bank via Getty Images)

Secret gags in "Seinfeld" are real, and they're spectacular.

There are Superman figures slyly appearing in episodes, writers dropping in the names of their friends and tons of hidden references the show creators even forgot were there. Well, now we know of at least one more.

When "The Chinese Restaurant" episode aired on May 23, 1991, NBC was not a fan. Larry David has said the network "hated" the episode and didn't think waiting around to get a seat in a restaurant would work as a storyline. Now, it's recognized as one of the most iconic episodes, and it turns out its most memorable joke has been an Easter egg this whole time, according to former "Seinfeld" writer Spike Feresten.

"Like Deep Throat ... This goes all the way to the top," said Feresten, who went on to reveal the famous line's hidden meaning to The Huffington Post.

The Joke: "Who's Cartwright?"





Image: YouTube



In the episode, George is waiting for a woman to call him at the Chinese restaurant. When she does call, the host calls out "Cartwright" instead of George's name. It's super hilarious and prompts this discussion between Jerry and George:

JERRY

Who's Cartwright? GEORGE

I'm Cartwright ... JERRY

You're not Cartwright. GEORGE

[EXPLODING] Of course I'm not

Cartwright ...

It has been a mystery for 24 years, but now, thanks to Feresten, we know who the real Cartwright is.

The Big Reveal: "Costanza (sounds like) 'Bonanza' = Cartwright"



Yep. This whole time Cartwright has been a reference to the classic Western show "Bonanza," which followed the wild adventures of the Cartwright family.

Though the episode happened before he joined the show, Feresten says the info comes from "an unimpeachable source." The writer was mum on if it was in fact one of the show creators -- either David or Jerry Seinfeld -- but, as we mentioned, did say it went "all the way to the top."

Whoa.