The story and script for Black Panther: Wakanda Forever had to change. Without his main character, it would take more than just a simple rewrite for the sequel to work. But while the script had to change, the tone didn’t change as much as you might think, according to director Ryan Coogler in a new interview with Inverse.

Chadwick Boseman propelled Marvel’s Black Panther movie to the top of the movie charts, making it one of the highest-grossing movies of all time and turning what was long considered a B-tier character into a household name. Then, in 2020, he died of colon cancer. Neither the film’s cast nor Marvel Studios executives were willing to consider reprising the character of T’Challa.

“The tone was going to be similar,” Coogler said of Wakanda Forever’s original script. “[T’Challa] I was going to mourn the loss of time, you know, coming back after being away for five years [after the ending of Avengers: Infinity War]. As a man with so much responsibility for so many, returning after five forced years of absence, that’s what the film was about. He was grieving for a time that he could not recover; pain was a big part of that.”

Some important details remain from the original script. Namor the Sub-Mariner “was always the antagonist,” Coogler said. However, other things had to change.

“Who the lead was, the lead’s flaws, what the lead was dealing with on his journey, all of that had to be different because of us losing him and the decisions we made about moving on,” said Coogler, who said making Wakanda Forever without Boseman is “the hardest thing I’ve ever had to do in my professional life.”

Black Panther: Wakanda Forever is expected to be a box office success, earning $175 million or more during its opening weekend alone. Wakanda Forever also stars Angela Bassett, Tenoch Huerta, Martin Freeman, Danai Gurira, Lupita Nyong’o, Letitia Wright, and Winston Duke. Ryan Coogler directed the film and co-wrote it with Joe Robert Cole. The film opens on November 11.