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Gunther always reserved the table for Rachel - A common fan theory, and not very far-fetched. The audience always knew that Gunther was obsessed with Rachel, so it's actually quite likely that he reserved the table at Central Perk to make sure that she always came in. You can even see the sign on the table.

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Monica's cleaning stems from fat camp - Not exactly an uplifting theory: fans have suggested that Monica's OCD cleaning tendencies may have resulted from fat camp and the attempts to control her weight/eating ever since.

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Mr. Heckles was murdered - A hilarious addition to the apartment building, the series devoted a whole episode to Mr. Heckles' death. However, what if he didn't go calmly into the night? He mentions that he's having a dinner party the night he dies, and there's a lot of banging. Could it have been signs of a struggle?

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Ross lost custody of Ben - When Ben didn't appear after season eight, it was suggested that Ross lost custody of his son due to all of his crazy antics (anger management issues, sleeping with his student, trying to figure out tactics to scare women, etc.). We can't really blame Carol for being concerned!

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It was all in Phoebe's head - One of the darkest theories out there, fans have theorized that secretly the whole series was imagined by Phoebe. She's still living on the streets and glances in the coffee shop at the group, imagining what her life would be like if she were friends with them. The added detail? Her twin sister Ursula is actually her reflection in the glass.

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Rachel is crazy about feet - A redditor suggested that Rachel has a foot fetish. She mentions toes as an erogenous zone when she and Monica are explaining what erogenous zones are to Chandler, and it's revealed that she likes painting Ross' toenails. Could that be Rachel's thing?

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Phoebe is secretly a genius - Despite Phoebe's upbringing and lack of any formal education, she is shown to be quite smart when it comes to dealing with her friends. She calls herself the "puppet master of the group," and frequently makes up plans to trick or coax her friends into doing something without their knowledge.

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Erica knew about the twins ahead of time - Given that Erica had a sonogram of the babies, and that the doctors likely would have mentioned something, that makes it unlikely that she didn't know she was having twins. Perhaps she was afraid to tell Chandler and Monica, assuming they would back out if they knew.

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Ross dyes his hair - It is slightly suspect that dark-haired Ross ended up with two fair-haired children. They do make fun of how much gel Ross uses on occasion during the show, so maybe he cared more about his hair than we thought and was actually dying it the whole time!

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Ross and Rachel had a bad luck streak - Many superstitious people out there know that opening up an umbrella indoors is bad luck. In the pilot, when Ross sees Rachel in September 1994, his umbrella opens up in the coffee shop. This would lead to a seven-year streak of bad luck, and a tumultuous relationship for the two of them, which theoretically ended with Rachel announcing her pregnancy in September 2001.

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Richard sabotaged Chandler - Richard didn't just randomly jump in on Monica and Chandler's date night. He felt the ring box in Chandler's pocket when he hugged him, so he interrupted their anniversary dinner and was quick to tell Monica afterward that he was ready to commit.

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The three different routes to motherhood were on purpose - All three of the women in the group dealt with pregnancy in different ways. Phoebe was a surrogate for her brother and sister-in-law's children, Monica adopted her twins after their mother gave birth to them, and Rachel gave birth to Emma. Many have theorized that the show's creators did this on purpose in order to show that each method to motherhood is valid.

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Phoebe and Joey were sleeping together - It actually kind of makes sense since everyone else is paired off. This theory was mentioned by Matt LeBlanc himself, stating that Phoebe and Joey could have been having casual sex the whole time (until Mike came around).

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The whole series is Rachel's anxiety dream - Rachel kicks off the show by running away from her own wedding. What if the whole series is just Rachel daydreaming about what things would have been like if she hadn't decided to go through with it?

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The triplets were actually Phoebe's kids - While pregnancy lengths vary wildly on the show (Carol's taking around two years and Rachel's pregnancy being longer than a year), Phoebe's was the only short pregnancy. According to the show, she was only pregnant for about four months, leading fans to believe that she may have already been pregnant before her brother asked her to be their surrogate, but she gave up her biological babies for Frank and Alice anyway.

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Monica actually got pregnant on her own - Courteney Cox was not the first actress to get pregnant during the show's run, but the weird part was that they didn't try to hide it. Some have suggested that the writers purposefully let audiences see her pregnant belly in season 10, suggesting that she and Chandler actually managed to get pregnant on their own.

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Mark was trying to break them up all along - Rachel and Ross frequently fought about her co-worker Mark. He does end up asking her out after they finally break up, but what if he planned all those late nights at the office to put their relationship on the rocks?

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Joey's evil plan for pancakes - While Joey may not be the smartest of the bunch, he undoubtedly loves food. In an episode starring Kristin Davis from 'Sex and the City,' fans have theorized that he only pretended to like her so that when she broke up with him Rachel would make him pity pancakes. The plan worked, and Joey perked right up when he heard he would get his breakfast food after all.

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It's all one big flashback - Much like 'How I Met Your Mother,' the whole series could be told from the characters in the future. The episode titles add to this idea, as they're framed like they're talking about a memory ('The One Where/With...').

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Emily was pregnant with Ross' child - The actress who played Emily, Helen Baxendale, was actually written out of the show earlier than planned due to her own pregnancy. But what if her character was pregnant too? Maybe she was going to tell Ross after the wedding, but since she couldn't trust him anymore after he said Rachel's name at the altar she decided to keep it to herself.

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Monica cheated on Chandler - A devastating idea, several fans have used clues in the show to suggest that Monica may have cheated. The fact that she encourages Chandler to flirt is commonly cited as proof. We're not so sure we're convinced.

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Ross and Monica had to be related - Ross isn't the most-loved character of the group, and many fans of the show actively dislike him. That's why he and Monica had to be related. He needs to bring Chandler to Monica's building, so he can get Joey as a roommate. The 'Friends' group wouldn't have happened without him, but if they weren't related, we're not so sure that he would have stuck around...

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TIt's an imaginary future -

Yet another meta theory, this one suggests that the gang are all high schoolers dreaming of how their lives would turn out. To some, this explains why everyone ended up achieving their goals in life. To others, they just attribute it to being a sitcom.

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Chandler tricked Monica to get her apartment - The theory posits that Chandler cheated in the first round of their contest, checking what was in Rachel's shopping bag so he would win. He knew that Monica's competitive streak would keep pushing her further and further, until she finally bet her apartment.

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Chandler created 'Riverdale' - Yet another series overlap, this theory uses the knowledge that Chandler wanted to write comics and Ben may have acting aspirations (due to the soup commercial). It suggests that once Chandler goes into advertising, he persuades Archie Comics to create a teen drama series, and casts his nephew as one of the main characters, Jughead. In case it escaped you, Cole Sprouse plays both Ben and Jughead.

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They're actually in a mental hospital - The coffee shop is the cafeteria and their apartments are their rooms. Each one is working through their own issues, and the whole series is just representative of combined delusions. This theory seems pretty far-fetched, but who knows?

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Starbucks had a hand in the show -

What better press could Starbucks have asked for? It's a group of people that rarely go out to bars or clubs, and spend all of their time at their local coffee shop with some comfy-looking furniture. Could the coffee chain have had a hand in the show?

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'Friends' and 'Parks and Rec' are in the same universe - There are several crossover theories with 'Friends,' but this one has Rachel sleeping with a 'Parks and Rec' character. Monica lists Ben Wyatt as someone Rachel slept with on the first date. The ages add up, so who knows?

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Ross and Rachel may have had different definitions of "break" -

Ross says that he lost his virginity to Carol and then married her. However, later in the series it's revealed that he slept with the cleaning lady in college. Maybe Ross and Carol went on a break at some point, trying out other people before getting back together, which would explain why Ross thought it was okay to sleep with copy girl. Could the biggest debate in TV history come down to this?

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