More than a decade after the final episode of "Friends" aired, a fan's theory on what the sitcom was really about is making its way to social media and going viral. The alternate ending could be heartbreaking for some dedicated fans.

A Twitter user has turned the whole series on its ear.

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Instead of the final shots of Monica, Chandler, Ross, Rachael, Joey and Phoebe closing the door and saying goodbye to the famous apartment and heading to their favorite coffee shop, Central Perk, there are only five friends. Phoebe is missing from the shop, Time reported.

In the alternative ending, Phoebe was not part of the coffee group, but instead someone looking through the window of the shop, watching strangers go on with their lives. The whole series was the figment of Phoebe's meth-addict imagination.

Wait, what?

Yes, Twitter user @strnks proposed that Phoebe was a homeless person who was addicted to drugs.

The final episode aired on May 6, 2004, but the show lives on in syndication and on streaming services.