Watch: Martin Freeman on making Black Panther: Wakanda Forever without Chadwick Boseman
Boseman, who played the title role in the first Black Panther film in 2018, passed away in 2020 at the age of just 43 due to colon cancer — a diagnosis he had kept secret.
Freeman, who returns to the cast for the sequel as CIA operative Everett K. Ross, said Boseman's passing was something the cast had to reckon with while making the new film.
"It didn't make it extra difficult. It made it slightly more poignant, I suppose, being back on set having lost Chadwick," he told Yahoo UK.
Freeman added: "To be honest, if we'd lost anybody it would have been horrendous. It's always horrendous to lose people when they're young.
"Added to that, we were losing Black Panther in Black Panther. That's a massive, massive thing — as well as just losing the man that Chadwick was.
"The truth is that you then just motor on. You've got a film to make. You've got X amount of pages to get through a day and you have to get through it. You don't get through it by being in a constant state of mourning.
"The shock of losing Chadwick was a while before we started shooting again, and that was awful. But hopefully by the time we started shooting it, we were in a mode of 'yes we've lost Chad — dreadful — and we've had to do a 90-degree turn and make this slightly something else'. I hope we've done that well."
Wakanda Forever sees numerous supporting characters from the first movie stepping up into larger roles, showcasing the strength of the franchise's ensemble cast.
"You had a leading character and a leading actor, but it's not like everybody else is just in the background," said Freeman.
He added: "There were very front-foot performances, in the first film as well. There's a core ensemble of very good characters and very good actors that can be called on again and were called on again. We're lucky with that."
Wakanda Forever follows the people of Wakanda dealing with the death of their king, while also managing the threat posed by sea-dwelling ruler Namor.
Freeman's role this time around features Ross trying to defend the rights of Wakanda amid a more hostile global atmosphere, with the actor called upon less often for action scenes.
The star said: "There's little bits. I like action and I also like the talky bits. I like running around and driving, but I also like talking and emoting and feeling my feelings.
"I think that's what Marvel does quite well. You do also care about characters. I don't think Marvel has ever just been a spectacle thing.
"It does the spectacle really really well, but it has characters you care about and characters you empathise with and laugh with. Going back to Iron Man, they were doing that really well."
Ryan Coogler is back in the director's chair for Wakanda Forever, with the world of the franchise set to expand with an upcoming Disney+ series set in Wakanda.
Sooner than that, though, the character of Riri Williams — introduced in Wakanda Forever and played by Dominique Thorne — will lead her own TV series, entitled Ironheart after her superhero alter ego.
Read more: Every upcoming movie and TV show in the MCU
As well as Freeman, the returning cast for Wakanda Forever includes Letitia Wright as Shuri, Angela Bassett as Ramonda, Lupita Nyong'o as Nakia, Danai Gurira as Okoye and Winston Duke as M'Baku.
Black Panther: Wakanda Forever is in UK cinemas and IMAX from 11 November.
Watch: Trailer for superhero sequel Black Panther: Wakanda Forever