The Biggest Plot Holes In Friends

The very first episode of "Friends" introduces Ross as a heartbroken husband going through a recent divorce from his seven-year marriage to Carol, his high school sweetheart. The reason for the divorce isn't because of the usual irreconcilable differences, but rather a very similar interest the two have — a sexual preference for women. What further complicates Ross' situation is that Carol tells Ross she's pregnant in the second episode, "The One with the Sonogram at the End." Ross, Carol, and Carol's love interest Susan form a confusing parenting triangle that dominates the rest of the first season, as if Ross and Susan didn't already have a complicated, resentment-fueled relationship of their own.

Since it usually takes two-to-three weeks after conception for a pregnancy test to come up positive, we can assume that Ross and Carol had been intimate just a few weeks before the pregnancy announcement. However, Ross learns that Carol is a lesbian in the Season 3 flashback episode aptly titled "The One with the Flashback," which takes place precisely one year before the show's pilot episode. This raises the question of how they could have had been physically intimate with each other a year after realizing Carol's sexual orientation, particularly given that Carol was already dating Susan.

While the show doesn't explicitly mention when they divorced, considering that an uncontested divorce in the state of New York typically takes three months, we can estimate that it occurred within the year prior to the show's debut. It also raises more questionable implications about whether Carol had cheated on Susan when she had sex with Ross, further complicating the timeline of their relationship. The circumstances behind their child's conception are never discussed or brought up.

The numbers of Monica, Chandler, and Joey's apartments are very minor details that would normally go unnoticed, but after watching "Friends" multiple times, the numbers become a notable detail. In the first few episodes of the series, Chandler and Joey's apartment number is "4" and Monica's apartment number is "5." However, the numbers turn to "19" and "20" a few episodes later. The sudden change goes unexplained in the show, although there is a popular theoretical explanation for it.

The apartment numbers being "4" and "5" would have meant that the friends lived on the first floor of the building shown through establishing shots to be 90 Bedford Street, which wouldn't have made sense as the view of the window in Monica's apartment makes it seem as though they live higher up, especially when they routinely peep down into Ugly Naked Guy's window across the street. To rectify this continuity issue, the show's creators and set designers might have created another inconsistency by quietly changing the apartment numbers to "19" and "20," hoping that no one would bat an eye. Given the options, maybe making the change was a better choice than pretending an apartment on the fourth floor could have a single-digit number, especially when we frequently see the characters climb several flights of stairs to get to their apartments.

Fans can argue that compared to other pairings between the six friends, Chandler and Rachel had only a handful of memorable interactions and storylines together, such the one where Chandler has a relationship with Rachel's boss Joanna and finds himself handcuffed in her office, begging Rachel to help him out. Rachel often admits that out of the three male friends, Chandler is the one that she likes the least. When Joey casually asks her who she'd like to punch among the friends, Chandler's name pops up in her mind. When given a choice between kissing Joey and Chandler at a New Year's party, she instinctively rejects Chandler.

The pilot episode of "Friends" makes it seem like it's the first time Rachel meets Chandler, and the only two friends she's met previously are Monica and Ross. Rachel evens remarks that she thought Chandler was gay until an incident involving breasts at Phoebe's birthday party indicates otherwise.

But there are several instances shown where the two had met long before their supposed introductions at Central Perk. In the Thanksgiving flashback episodes, Chandler visits Ross' parents' home for the holiday where Monica's best friend Rachel is also present. She helps Monica scheme her revenge against Chandler a year after he calls Monica "fat." At a college party that Rachel and Monica sneak into, Chandler kisses Rachel as an act of revenge against Ross after Ross breaks their agreement to not pursue a girl they both like. In a separate incident, the two cross paths again exactly a year before the events of the pilot episode, where Rachel visits the bar (which later turns to Central Perk) that Monica and Chandler frequent. While it's made to look as though Chandler and Rachel are about to hook up, they've somehow forgotten each other, again, by the time of Episode 1.

When our beloved characters go through significant life events — such as weddings, child births, and funerals — it's difficult to not notice that certain secondary characters previously established as important are absent from these events and go unmentioned. Of course, there are behind-the-scenes explanations for their absences; sometimes it is difficult to remember characters who made brief appearances in previous episodes, or those characters just don't fit in amid the ensemble cast that's already present at a major wedding episode, or actors are simply difficult to get on short notice.

Phoebe finding her birth mother is a major story event in Season 3, but after appearing in a few subsequent episodes and being relegated to off-screen duties such as sending Phoebe a fur coat in Season 5, the character is largely forgotten. Same goes for Phoebe's birth father, whose sudden appearance in the Season 5 episode "The One with Joey's Bag" acts as an emotional payoff for the seemingly orphaned Phoebe, and never appears again or is even mentioned afterwards. This strikes the audiences harder during the season-long storyline of Phoebe's wedding with Mike, where multiple close family members — including three Phoebe gave birth to herself — remain absent with no explanation.

Fans have even noted that Ross' son Ben is noticeably absent in significant events of his father's life, such as his wedding with Emily, and especially the birth of his step-sister Emma. It would've been endearing to see Ben meet his sister and could've made for interesting storylines where Ross has to manage having two children from two separate marriages. But some cast members had interesting theories surrounding Ben's disappearance from "Friends" – Ben's actor Cole Sprouse suggests that Ross was "never really the most present father."

On the flight to Vegas, Ross and Rachel are still reeling from an awkward encounter the previous evening when Ross thought Rachel's nakedness in her apartment was a hint that she wanted sex with him. Rachel teases Ross about it, and the two go on a prank contest on each other on the plane that ends with Ross drawing a mustache on Rachel's face with a pen while she's asleep. She finally sees the mustache on her face when they reach the hotel in Vegas, causing Rachel to frantically try to remove the mustache from her face to no avail. She gets mad at Ross and the two decide to stay in the room to spare Rachel any more embarrassment. They get really drunk, Rachel draws on Ross' face, and the two get married. When they wake up the next day, they fail to remember their drunken marriage until the group reminds them.

While Rachel has a hard time trying to remove the mustache Ross draws on her face, the ink on both their faces is gone the morning after their wild night. This plot hole is significant because the ink on Rachel's face sets off a chain of events that eventually lead to her and Ross getting drunk and getting married. This becomes one of the most memorable running gags on "Friends" ("Three divorces!") and the beginning of a multi-episode arc where Ross refuses to tell Rachel they are still married despite his promise to have their union annulled.