The Friends Star That Fans Thought Should Have Been In The Reunion

"Friends: The Reunion" has quite an impressive list of guest stars, which includes some of the biggest names in the entertainment industry. The highly-anticipated special will see Courteney Cox, Jennifer Aniston, Lisa Kudrow, David Schwimmer, Matt LeBlanc, and Matthew Perry come together, as they sit down and reminisce on the sitcom that shot them to superstardom in the mid-'90s and early 2000s.

According to The Hollywood Reporter, joining them on stage for different points during the special will be David Beckham, Justin Bieber, BTS, James Corden, Cindy Crawford, Cara Delevingne, Lady Gaga, Elliott Gould, Kit Harington, Larry Hankin, Mindy Kaling, Thomas Lennon, Christina Pickles, Tom Selleck, James Michael Tyler, Maggie Wheeler, Reese Witherspoon, and Malala Yousafzai. Some of these megastars served as recurring or guest stars on "Friends" over the years, while others appear to be totally random. Those who were never involved in the series — like Bieber, for example — are self-proclaimed superfans who joined part of the special to talk about what the show meant to them.

The response to the guest list has been mixed on social media, with many wishing the guest stars were just limited to those who had appeared on the show. Another major issue some fans had was that there were some very important "Friends" recurring characters who are not on the guest star list. One omission in particular really has the fandom upset.

Paul Rudd will not appear in the Friends reunion special

Some of the guest stars set to appear on "Friends: The Reunion" are actors who portrayed some of the love interests of the six main characters. Tom Selleck, who played the lovable ex of Monica, Dr. Richard Burke, is set to appear, while Janice Litman-Goralnik (Maggie Wheeler) herself will also be in attendance.

Shockingly absent from the list is Paul Rudd, who played Phoebe's boyfriend-turned-husband Mike Hannigan from Season 9 to Season 10. Rudd appeared in a whopping 17 episodes of the series, but won't be showing up for the reunion. "I wanna know why we're getting Justin Bieber instead of Paul Rudd," one fan wrote on Twitter. "So they're doing the #FriendsReunion without PAUL RUDD?! LIKE HOW AND WHY," another asked.

It's entirely possible, and more than likely, that Rudd was asked to appear at the reunion, but couldn't make it due to scheduling conflicts. It would be shocking to find out he wasn't asked to attend, especially given the fact that his character married one of the main friends. However, he's far from the only recurring character not to make it to the list of guest stars, as Aisha Tyler and Cole Sprouse also won't be appearing.