Meryl Streep joins cast of Only Murders in the Building for season 3

The Only Murders in the Building cast has just added another iconic actor to its ranks - the one and only Meryl Streep.

In what will go down as one of the most memorable casting reveals of all time, the three-time Oscar winner revealed she's now part of the show in the most adorable way. Watch the big reveal below:

Selena Gomez, who stars as in the mystery comedy-drama as Mabel Mora, shared a TikTok from the set of season three.

The singer was joined by her co-stars Steve Martin, Martin Short, and Paul Rudd, who had joined the show at the end of season two last year.

Then suddenly, the Mamma Mia! and The Devil Wears Prada star pops up from behind Martin, offering him a pillow before placing it behind his back. She then asks her new co-stars if they need anything like a personal assistant would.

We're mind-blown and so is Selena, who turned to the camera and gasped after Meryl made her big debut.

Meryl's character has yet to be named but if she's in costume in the clip above, then we're expecting to see a very sleek pulled back hairstyle that Miranda Priestly would approve of.

@hulu/Instagram

Fans of the show are in a state of shock and shared their excitement in the comments.

One person wrote: "Meryl Streep, Paul Rudd, selena gomez, Martin Short and Steve Martin all together in a show? I couldn’t ask for something better than this!!!"

Another thrilled viewer penned: "MERYL STREEP!!!! WHATT!!"

While a third fan created a brand new name for the show. "ONLY LEGENDS IN THE BUILDING," they wrote.

A fourth TikTok follower shared: "NOT MERYL STREEP POPPING UP??? literally the most iconic cast!"

And a fifth added: "MY JAW IS ON THE FLOOR."

The official Hulu Instagram account also confirmed the legendary casting with a behind-the-scenes black and white snap.

In October, Hulu also confirmed Jesse Williams - the actor best known for his role as Dr Jackson Avery AKA everyone's crush in Grey's Anatomy - will be joining the show for season three in a recurring role.

The actor will play a currently an unnamed documentarian with a 'particular interest in the case that Selena Gomez's Mabel Mora, Steve Martin's Charles Haden-Savage and Martin Short's Oliver Putnam are working on'.

In case you haven't watched it yet, the critically acclaimed show follows three strangers who share an obsession with true crime - before suddenly finding themselves wrapped up in one as they investigate the mysterious death of a neighbour within their Upper West Side apartment building.

Sipa US / Alamy Stock Photo

Season two saw the team unveil the killer of Bunny Folger, but it didn't come without its difficulties, as the friends had to grapple with neighbours who all think they were responsible for her death.

Season three is expected to air later this year on Hulu in the US and on Disney+ in the UK.

Seasons 1 and 2 are available to stream on Disney+.