Amanda Seyfried said Meryl Streep is "very much a part" of 'Mamma Mia!: Here We Go Again!"
Fans began speculating the fate of Streep's alter-ego Donna Sheridan after the trailer for the new movie hinted that her character had passed away, but Seyfried, 32, has now teased that the Academy Award winning actress still has a big role in the film.
Seyfried - who plays Streep's on-screen daughter Sophie - told Entertainment Tonight: "You do see her. She's, Meryl is very much a part of this movie.
"No, there are absolutely no flashbacks. No, because all the 'flashbacks' are of Lily [James] playing Donna.
"So it's a prequel and a sequel, and so you see Meryl is very much a part of it."
Seyfried stars alongside Streep, 68, Colin Firth, 57, Stellan Skarsgard, 66, Pierce Brosnan, 64, Dame Julie Walters, 68, and Dominic Cooper, 39, who are all reprising their roles from the first movie.
'The Best Exotic Marigold Hotel' scribe Ol Parker has written and directed the Universal Studios film, while Playtone Pictures, which produced the first instalment, jumped back on board.
'Mamma Mia!' focused on a bride-to-be Sophie (Seyfried) trying to find her real father so that he can walk her down the aisle at her wedding to Sky (Cooper).
But she gets a shock when she discovers that there are three potential men that could be her biological dad.
And Seyfried said it felt like a "weird mind trip" returning to play Sophie in the sequel - which is slated for release this year 10 years after the first movie - because she is a "bonafide adult".
She said: "It was like such a weird mind trip 10 years on. Like, I'm an adult now, real bonafide adult with a baby, and these people related to me in such a different way.
"And we all got along so well. It was so much like family and now they've seen me kind of grow up."
The new movie will focus on Sophie finding out more about her mother's past while seeking guidance on how to handle her pregnancy.
It has been reported that the film will show how Donna met the three men; Sam Carmichael (Brosnan), Harry Bright (Firth) and Bill Anderson (Skarsgard) in the years before the original story takes place with James taking over the role.
The new film will also feature music legend Cher as Sophie's grandmother.