Trivia
In The One With The Superbowl Part 2 the gang are down at the movie set of Marcel's film. Joey asks Phoebe to walk with him so he can show off his acting skills to the director. If you look closely you can see that the 'director' and the people surrounding him are the actual producers of Friends - Kevin S. Bright, Marta Kauffman and David Crane. See more...
Movie Mistakes blog
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Other great sites
Friends (1994) - 1 mistake in "The One Where Old Yeller Dies"
starring Courteney Cox, David Schwimmer, Jennifer Aniston, Lisa Kudrow, Matt LeBlanc, Matthew Perry (add more)
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Series 3