"The One Where They Get Back Together" is finally upon us -- and the cast of "Friends" will be joined by famous fans from Justin Bieber to David Beckham, HBO Max announced Thursday.

The long-delayed and much-hyped reunion, billed as an "unscripted celebration" of the US smash hit television sitcom, will debut on May 27, the streaming platform said in a statement.

A brief trailer for "Friends: The Reunion" showed the six cast members walking slowly away from the camera with their arms linked together, while the iconic "I'll Be There For You" theme song plays gently in the background.

"Friends" -- starring Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc, Matthew Perry and David Schwimmer -- remains wildly popular even among viewers too young to remember its original run, which ended in 2004.

Parent company WarnerMedia had hoped the reunion would be ready in time to launch its Netflix-rival HBO Max platform last May, before the coronavirus pandemic scuppered production.

It will now arrive on screen exactly one year after the streamer's launch, with its stars reportedly earning $2.5 million each for taking part.

In addition to the original cast, the reunion will feature guests including soccer legend Beckham, pop stars Bieber and Lady Gaga, K-pop sensation BTS and fashion icons Cindy Crawford and Cara Delevingne.

Tom Selleck -- who appeared in 10 episodes as a love interest of Monica (Cox) -- will take part, as will Reese Witherspoon, who played the sister of Rachel (Aniston).

The reunion was filmed at Stage 24 on the Warner Bros Studio lot near Los Angeles, which also served as the original soundstage for the sitcom about a group of close-knit New York friends navigating adulthood.

A remote or virtual reunion was never considered due to the significance of the original soundstage, producers have said.

"Friends" executive producers Kevin Bright, Marta Kauffman and David Crane also returned for the special.