The following post contains spoilers for the plot of Mamma Mia! Here We Go Again.

Even with the warning above, we suggest you pause for a second to consider if you really want to know what happens at the beginning of Mamma Mia! Here We Go Again. Are you sure? Are you certain? Are you ready to take a chance on this? Okay, yes, fine, as the movie’s trailers implied, they killed Meryl. Donna Sheridan is dead, long live her hotel on the made-up Greek island of Kalokairi.

You can rest assured that Streep, who still appears in new scenes in the movie, was fine with the decision — and according to director Ol Parker, it wasn’t because she had other scheduling obligations. “If it had worked out that Meryl was going to be the lead for the whole thing, then they would have waited for a time when Meryl could be the lead for the whole thing,” Parker said. “It was about finding the best story to tell that worked for everybody and this was the story we settled on.”

So, why, why is Donna Sheridan dead? Blame Richard Curtis, his daughter Scarlett, and The Godfather Part II. One day, out of the blue, Parker, who wrote the Best Exotic Marigold Hotel movies, got an email from Curtis, the man behind Notting Hill and Love Actually, that read, “Random question: do you like ABBA?” “I thought he was going to invite me to dinner with Benny Andersson, since he knows everybody,” Parker said. Instead, Curtis, who had been talking with the Mamma Mia! producers, wrote back, “Chance of you writing a sequel?”

Amazing. That would be a hoot, Parker thought. But he didn’t have any ideas. Curtis did, though — or, rather, his daughter did. “When the call from the producers came to him he was driving along with his daughter Scarlett and he wondered aloud what the story could be,” Parker said, and Scarlett suggested the story “should be Godfather II” — as in a sequel that’s really a prequel. Curtis passed that idea along to Parker, who got excited about the idea of exploring the backstory hinted at in Catherine Johnson’s plot of the original. Why not go deeper into Donna’s diary?

To make it work, however, he knew Donna had to die. “I think it’s the most meaningful and emotional and impactful way to tell that story and this was my suggestion,” he said of his pitch to both producer Judy Craymer and what Parker said everyone calls the “legacy cast” of the original movie. “Obviously it was greatly discussed with everyone and Meryl was thrilled and delighted with it.” (In the end, the plots of Here We Go Again and The Godfather II really do parallel each other well: Lily James is Robert De Niro, the young version of the last film’s patriarch/matriarch. Amanda Seyfried is Al Pacino, shoring up the family business in the present — in this case, that business is a hotel in Greece, not the mob.)

To write the rest of the movie’s plot, Parker worked his way through the “puzzle box” of Mamma Mia!’s admittedly complex setup: How do you find a way to convincingly have your lead character have sex with three men within a short period of time, and make each event meaningful? “My job was to give her slightly different reasons for each of the men,” Parker said. “Young Harry is comedy and a slight pathos and also charming. Young Sam is a love story. Young Bill is to help her feel better from having a broken heart.”

They also needed someone who could make a convincing young Donna. For that, Parker insisted on Lily James, who was stuck on the Baby Driver publicity tour while Mamma Mia! was casting, which kept getting extended because that movie did so well. “We were seeing all these brilliant people and I was like we’ve got to wait, because this girl is amazing” Parker said. They did, and once James came in to audition, “I knew it on a handshake.” “It’s obviously a testament to the extraordinary performance of Lily James that you never judge Donna,” he said. “Like Meryl in the first one, you just go with it and you take it as a sign of life and vitality and excitement and joy.”

After Parker’s work on the script, he was surprised as anyone that he also ended up directing the movie. “I imagine several people turned it down, but never told me,” he said. As the producers started to schedule shooting times with the legacy cast, and started to cast the younger cast, “I was like, ‘Who is directing this?’” Parker said. “Judy Craymer was like, ‘We thought you might.’ I pretended I was delighted. Of course I was terrified.”

“If I’d known I’d be directing the movie,” he added. “I never would have written a dance sequence on a floating boat.”

The Story Behind Meryl’s Mamma Mia! Here We Go Again Plot