The actor, whose 2020 death sent shockwaves rippling through the world, is pictured in a 2018 photograph that Nyong'o shared on social media Monday.
"Three years ago today, I experienced a singular pain at the news of @chadwickboseman's death," the actress captioned the photo. "The confusion was so profound that it took months to trust the feeling of joy again."
She continued, "This is a photo I took on film at the airport as we arrived in South Korea in 2018. We had just learned to do the baby heart with our fingers. Here Chadwick was adding his suave flare. We spent a glorious 72 hours there, and the memory fills me with so much joy."
"Death is hard to understand, maybe even harder to accept," Nyong'o said. "But the love generated from the life he lived will fuel every anniversary marking his absence. Chadwick may no longer be in our photos, but he will always be in our hearts."
Boseman died of complications after a private four-year battle with colon cancer in 2020. In the aftermath of his death, Nyong'o penned an emotional letter shared on social media, writing that though she "didn't know [Boseman] for long," he still had "a profound effect" on her.
"When we came together to make Black Panther, I remember being struck by his quiet, powerful presence," she wrote. "He had no airs about him, but there was a higher frequency that he seemed to operate from. You got the sense that he was fully present and also somehow fully aware of things in the distant future."
She continued, "He set the bar high by working with a generosity of spirit, creating an ego-free environment by sheer example, and he always had a warm gaze and a strong embrace to share."
Alberto E. Rodriguez/Getty Images Lupita Nyong'o and Chadwick Boseman
During his two-decade career, Boseman received various accolades for films including 42, Da 5 Bloods, and Ma Rainey's Black Bottom, but he was best known for his history-making role as T'Challa, the first Black superhero to headline a film in the Marvel Cinematic Universe.
The Prince (and later King) of Wakanda made his debut in 2016's Captain America: Civil War before taking center stage in Black Panther, the Ryan Coogler-directed film that broke box office records and became the first superhero film to earn an Academy Award nomination for Best Picture. Boseman went on to reprise the role in Avengers: Infinity War and Avengers: Endgame, where he one again shared the screen with Nyong'o, Letitia Wright, Danai Gurira, and Winston Duke.
The Black Panther sequel Wakanda Forever arrived in late 2022, after being delayed and reworked in the wake of Boseman's death. It paid special tribute to the actor and his character, bidding farewell to both while marking a new beginning for others.
"The most important thing, of course, was honoring our brother, our leader, and our king," Gurira told EW ahead of the film's release. "That was definitely at the forefront of our minds and our spirits and our hearts. There was this amazing impact that the first Black Panther had, so the need, I think, was to really solidify that these characters and this world have an arc. It wasn't a one-time momentous thing."
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