Die-hard fans of Friends will swear they can correctly answer more questions about the hit sitcom than anyone else in the world.
What is Chandler's Dad's name?
Which Friends character had a pet hamster called Twinkles?
What does Joey have a framed poster of in his bedroom?
But if there's a group of people who might be able to trump your knowledge of Friends, it's the show's castmates.
This week, this theory was finally put to the test when real-life BFFs and Friends co-stars Lisa Kudrow and Courteney Cox appeared on Celebrity Name Game and took part in a 45-second-long quiz about the show.
From questions about Smelly Cat and Gunther, to where they drank coffee and the name of Monica's husband, the duo answered each question with just as much passion as a true fan of Friends.
We even got an insight into the stars' friendship when Courtney gives Lisa the clue, 'We had lunch with her every day,' to which Kudrow shouts, 'Jennifer Aniston!'
Er, could we love them more?
Watch the clip below: