The beloved Boseman is the subject of a video Nyong'o, 39, posted to her Instagram Sunday. The actor died on this day in August 2020 at the age of 43 of colon cancer. Fans around the globe were shocked and saddened by the news. The Marvel star kept his diagnosis private.

"Chadwick, what are you doing?" Nyong'o asked in the IG video, showing Boseman with a Sharpie in hand.

"I'm signing tickets. I signed somebody's shoes over there …" he said. The late actor joked that he signed "a pair of Jordans", even though he didn't play basketball.

In the video, a crowd of fans surrounded Boseman at a movie theater, and Nyong'o asked behind the camera, "why do you think they asked you?"

"I don't know!" Boseman replied. "I have no idea."

The caption of Nyong'o's post says "Kept it real, kept it kind"," in a tribute to her costar.

Winston Duke, who also stars in the Black Panther films, commented: "Incredibly generous man…always sharing abad helping and giving and loving… ugh… my heart … Ure missed beyond any words my brother… love love! Thanks, Lupita for posting our treasure… man oh man!! ??????"

Letitia Wright, who played the sister of Boseman's character in the Marvel films, also commented with three heart emojis.

The new installment in the Black Panther story titled Wakanda Forever will be released in November. Without Boseman, Nyong'o said, it was a challenge. Speaking with The Hollywood Reporter at San Diego Comic-Con in July, the actress opened up about filming the highly anticipated sequel to 2018's Black Panther after the loss of Boseman.

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Despite it being "a doozy of a few years for everybody," Nyong'o told THR that she was proud that they were able to make the film, calling the act, "a powerful statement unto itself."

"It was very therapeutic," she said. "It restored a sense of hope for me in making it, and I think we've expanded the world of Wakanda in ways that will blow people's minds — not just Wakanda, but the Black Panther world. It's going to blow people's minds, and I just cannot wait until it's not a secret anymore."

In July, Marvel debuted the first teaser trailer for Wakanda Forever. Nyong'o's character Nakia is the first onscreen, followed by appearances from Wright as Shuri in an all-white outfit and, later, in tearful scenes on the beach.

A synopsis of the film states that the characters "must fight to protect their nation from intervening world powers in the wake of King T'Challa's death."