Famous 'Friends' cliffhanger was originally a mistake

As any good "Friends" fan will know, the epic cliffhanger at the end of the show's fourth season was a big moment for Ross and Rachel's budding romance.

"I, Ross."

"I, Ross."

"Take thee, Emily."

"Take thee Rachel."

But, as one of the show's writers revealed on "The Story Behind" Wednesday night, Ross's pivotal mistake actually started out as just that - a mistake.

And it's all because of a slip-up David Schwimmer made during a different scene.

"His line was to come in and say, 'Emily, the cab is downstairs waiting,' something like that. And he walked in and said, uh, 'Rachel, the cab is downstair... Oh, BLEEP.' And I remember, I was standing next to David Crane, and I said, 'That's, that's it," said writer Greg Malins on "The Story Behind."

And that's how the writers decided to have Ross accidentally say Rachel's name during his wedding vows to Emily.

"Friends" fanatics on Twitter were just as thrilled to learn some of the hit show's secrets.

But, as we discovered Tuesday, David's mix-up wasn't "Friends'" only moment of pure fate.

Matthew Perry confessed on "Late Night" he almost missed his chance to audition for the role of Chandler because he was committed to another series. But that show tanked just in the nick of time.

Well, we think it's safe to say we'll be watching the entire series over again after this. You know, for research ...

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