Friends The Reunion: 6 best moments as Rachel, Ross, Joey, Phoebe, Monica and Chandler make an emotional Friends return, Lady Gaga sings 'Smelly Cat' duet and we learn how Matt Le Blanc really dislocated his shoulder

As the much-loved American sit-com reunion finally made its debut on Thursday, here is how people are reacting to the biggest moments of the show.

If you are not a fan of spoilers, beware as we delve into the Friends reunion special which revealed secrets about the show even die-hard fans may not have known.

The cast - Courteney Cox, Lisa Kudrow, Jennifer Aniston, David Schwimmer Matt LeBlanc and Matthew Perry - reminisced about their time together and pulled the curtain back on a TV juggernaut.

So what were the biggest moments and how did fans react?

David Schwimmer, from left, Courteney Cox, Matt LeBlanc and Jennifer Aniston in a scene from the "Friends" reunion special (Terence Patrick/HBO Max via AP).

Life imitates art for Jennifer Aniston and David Schwimmer

While their characters Ross and Rachel were involved in a high-profile love story, fans may not have known the actors who played them almost followed in their footsteps.

"The first season I had a major crush on Jen," Schwimmer revealed. "And I think we both, at some point, were crushing hard on each other but it was like two ships passing because one of us was always in a relationship and we never crossed that boundary. We respected that."

Aniston agreed and confirmed their first kiss came on screen when Ross and Rachel embraced at the Central Perk coffee house.

Matt LeBlanc, from left, Matthew Perry, Jennifer Aniston, Courteney Cox and Lisa Kudrow in a scene from the "Friends" reunion special (Terence Patrick/HBO Max via AP).

She said: "So we just channelled all of our adoration and love for each other into Ross and Rachel."

Following the reveal, fans took to twitter to express the high emotions this caused.

One twitter user said: “My heart is exploding”, another tweeter said: “My heart is so full. I was smiling throughout, I can’t stop the tears! Perfect. Just perfect.”

Matt LeBlanc suffered a nasty injury during episode filming

Season three's The One Where No One's Ready is best known for the moment Joey enters the room wearing all of Chandler's clothes.

But during the special it was revealed the episode also resulted in an injury for one of the cast members.

It included a storyline of Chandler and Joey arguing over a chair and required LeBlanc to jump onto the furniture.

The first three attempts went "perfectly," producers said, but the fourth resulted in LeBlanc dislocating his shoulder.

The incident was shown during the special.

After hearing about the dislocation, one fan said: “That looked like it hurt. Made me cringe a little bit and feel that pain.”

One fan even became superstitious as they pointed out: “Felt so bad for Joey the one time they didn’t do the huddle he dislocated his shoulder.”

Star-studded Smelly Cat duet

The star-studded special saw one of the world's biggest pop singers performing alongside a cast member.

Kudrow, in character as Phoebe, was seated on the Central Perk sofa, guitar in hand, for a rendition of her famous song Smelly Cat.

She was soon joined by Lady Gaga for a duet, before later being accompanied by gospel singers.

"Still think it's better when it's just me," Kudrow muttered.

Many seemed to react positively to the star-studded duet.

Liv Marks, Senior Entertainment Reporter for Bauer Media said: “I’m sorry but Lady Gaga can make Smelly Cat absolutely slap.”

Another listener said: “Never would I have ever thought I’d see Gaga and Lisa Kudrow sing smelly cat together in 2021. I’m so here for it.”

Monkey business

During a Q&A segment, the stars were asked if there was a part of the show they did not like.

"The monkey," Schwimmer replied, meaning Marcel, Ross' pet from the early seasons.

He revealed the animal would frequently mess up the cast's carefully choreographed moves, leaving otherwise perfect takes on the cutting room floor.

And worse, according to Schwimmer, Marcel's handler would feed him live bugs, which he would then eat and wipe his hands on the actor.

He said: "I would have monkey grubby hands all over. It was time for Marcel to f*** off!"

The audience created wedding bells

At the end of Friends, Monica and Chandler, happily married and having started a family, were moving out of New York City to embark on the next stage of their lives together.

However, that was not the original plan.

Producers revealed the "insane" reaction of the studio audience when it was first revealed Monica and Chandler had spent the night together convinced them to pursue the storyline, rather than leave it a one-off.

Friends co-creator Marta Kaufman said: "It was such a powerful moment that we knew we had to explore it more."

Although many people were shocked that a long-term relationship was not originally on the cards for Bing and Geller, many were glad the change was made.

One viewer said: “OMG!!! Monica and Chandler weren't supposed to be a couple??? So happy they changed that.”

Cameos from old favourites

As well as the original six, some of the show's best-loved supporting characters returned for the special.

They included Larry Hankin, who played noisy neighbour Mr Heckles. The barbershop quartet used by Ross to deliver a message to Rachel congratulating on her new job also made an appearance.

Joey's hand twin, played by Thomas Lennon, turned up to embrace LeBlanc while Tom Selleck, who starred as Monica's older boyfriend, Richard, also surprised the cast.

There was an emotional moment when Elliott Gould and Christina Pickles - who played the Gellers' parents - turned up in the studio audience.

And Maggie Wheeler - also known as Janice - appeared and performed her catchphrase "Oh! My! God!" while James Michael Tyler, who played Gunther, the coffee shop manager in love with Rachel, Zoomed in.

One viewer said: “Finished watching the friends reunion episode very emotional and brings back a lot of memories from my childhood when I grew up with it.

“One of my favourite shows of all time.

"It was so great seeing the original 6 and all the special cameos during the show.”

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