10 Friends Moments That Were Totally Unscripted
7. Billy Crystal & Robin Williams' Cameos
One of the strangest and most unforgettable Friends cameos occurs in the season three episode "The One with the Ultimate Fighting Champion," where Billy Crystal and Robin Williams appear as Tim and Tomas, two men who ask to squeeze on the friends' couch when Central Perk is crowded.
What follows is a baffling-yet-hilarious scene where Tomas explains to Tim that he believes his wife is cheating on him with her gynecologist, only for Tim to reveal that he is the very gynecologist in question.
This leads a tearful Tomas to end the friendship as the two storm out of the coffee shop, after which Monica (Courteney Cox) fails to remember the story she was half-way through telling when the pair interrupted them.
Despite the amount of dialogue involved in the brief scene, it was largely improvised by Crystal and Williams, who weren't even supposed to be in the scene at all.
As it turns out, the actors were shooting on a nearby set and wandered over to say hello, at which point the writers invited them to make an impromptu appearance on the show.
Crystal and Williams hashed out the particulars between themselves while shooting, and both Joey's interruption and Monica forgetting her story were also additional ad-libs thought up on the spot.
If you somehow needed any further proof that Crystal and Williams are all-time comedy masters, here it is.