In an interview for the former Late Show host's Netflix series My Next Guest Needs No Introduction recorded before the Academy Awards, Smith, 53, talked about his connection to his King Richard role — specifically, drawing from experiences with his own late father.
He also talked about taking a break from acting and writing his 2021 memoir, telling Letterman, 75, in the season 4 episode released Friday, "My experiences and my life, and the writing of this book have unlocked a part of me, as an actor, that is like nothing I've ever experienced."
"Life is so exciting to me right now because I can reach people differently than I've ever been able to reach people, largely because of my pain," Smith also said. "I'm really ready to dive into my heart in a way that I think will be, hopefully, fulfilling for me and helpful for the human family."
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Smith was banned from future ceremonies and related events for 10 years by the Academy for slapping Chris Rock onstage during the March ceremony after the comedian made a joke about Jada Pinkett Smith's shaved head.
Related video: Will Smith resigns from Academy after smacking Chris Rock during Oscars
He said in another moment of the Letterman special, "You can't protect your family — that's not real." The comment came when Smith was discussing realizations he's had over his life.
"Protection and safety is an illusion. You have to learn to live with the reality that any moment, anything can be gone in one second," Smith added. "So with that reality, how can you be here? And how can you be joyful and be here?"
The Letterman episode starts with the message: "This episode was recorded prior to the 2022 Academy Awards ceremony." The other guests on his show this season are Billie Eilish, Cardi B, Ryan Reynolds, Kevin Durant and Julia Louis-Dreyfus.
Since the incident, Smith — who went on to win Best Actor for his performance in King Richard — has publicly apologized to Rock, 57, saying that he "reacted emotionally" because the "joke about Jada's medical condition was too much for me to bear." (Pinkett Smith, 50, has been open about living with alopecia.)
My Next Guest Needs No Introduction is now streaming on Netflix.