Friends: The Reunion will air tomorrow night on Sky One, with the six original cast members returning to Warner Bros. studios to reminisce about their decade on the show.
As well as the Central Perk gang, some other familiar faces will appear in the reunion - much like the guest appearances of actors throughout the ten seasons of the show.
The cast have now shared some of their favourite guests from the original show - including Aniston who named her ex-husband as one of her favourites.
So, what did she say and who did the other five enjoy working with? This is what the Friends cast said about their best co-stars.
What did Jennifer Aniston say about Brad Pitt?
Speaking to Access about the reunion show, Aniston shared her favourite guest appearances alongside co-stars Lisa Kudrow and Courteney Cox.
After naming a few of her favourites and agreeing with Cox and Kudrow about other “fantastic” stars, she concluded that "Mr Pitt was wonderful”.
Aniston, who played Rachel on the show, added: "He was fantastic,” as she nodded her head.
Pitt appeared on the eighth season of the show, while married to Aniston.
They married in 2000 but divorced in 2005, as rumours circulated he had an affair with Mr and Mrs Jones co-star Angelina Jolie.
He later married Jolie and had six children with her; they divorced in 2019.
Pitt appeared in the Friends episode, 'The One with the Rumor', where he played Rachel's former classmate.
Aniston also praised Ben Stiller's appearance as "hysterical" and Reese Witherspoon – who appeared on the show as her on-screen sister Jill Green – as "brilliant".
Who were the other cast favourites?
Kudrow added that she was "blown away by so many" of the people who guest-starred on Friends, during its run between 1994 and 2004.
She also praised Stiller and Kudrow, describing Stiller as “really funny” and Paul Rudd as “incredible”.
Cox told how Tom Selleck was “just the most sweetest [guy]” with Aniston and Kudrow agreeing he was the “seventh friend” as he featured across two seasons. He played Richard Burke - Monica’s older boyfriend - in the American sitcom.
Aniston added that she felt Rudd could also have been one of the ‘friends’ circle.
The girls also commented that US comedian Aisha Tyler, who played Charlie Wheeler on the show, was “fantastic” and “so great”.
David Schwimmer (Ross), Matt LeBlanc (Joey) and Matthew Perry (Chandler) all mentioned Sean Penn, with Cox adding “having Sean Penn on your show, I mean..come on.”
Many others were also named in the interview.
When is Friends: The Reunion released on TV?Friends: The Reunion will be available for UK viewers from 27 May at 8am, on Sky One and NOW TV.