Sterling K. Brown Reveals the 1 Thing Mark Harmon Told Him That Changed His Whole Perspective: ‘The Nicest Man’ (Exclusive)

Sterling K. Brown knows that setting the tone comes from the top — and he learned that lesson from none other than Mark Harmon!

Speaking to PEOPLE ahead of the premiere of his new show, Washington Black, Brown says it was important for him to create an environment on set where everyone felt included, no matter how big or small their role may be.

“I have been on sets where I felt incredibly welcome and seen and it made showing up for work that much easier,” the This Is Us alum, 49, explains. “I’ve been on sets where I was like, these people could give a flying fig Newton if I’m here or not. And it may just seem like, ‘Okay, now I’m showing up to make this paycheck so I can qualify for my insurance.’ The former is much more appreciated than the latter.”

“And so I felt like when I had the opportunity to be someone who was — this was their home set, this is a place where people were coming and being guests, what have you — make them feel welcome, make them feel seen and appreciated, it makes the work easier,” he continues. “It makes the work easier, knowing that someone wants me here and someone is happy to have me here, so you don’t have to worry about that.”

“Now I can just focus on this thing that is this character, that is this storyline,” he adds. “How do I bring this scene to life in the best way possible? Knowing that I have people here who are rooting for me and wanting to see me succeed makes success an easier thing to achieve.”

Brown says he learned that lesson directly from Harmon after the NCIS actor treated him with the same type of kindness years ago.

Brown appeared on NCIS in 2013, portraying the role of Elijah Banner, while Harmon led the series as Leroy Jethro Gibbs from 2003 until 2022.

“I can remember, I did a guest spot on NCIS, and people will say this … Mark Harmon was the nicest man ever,” he says. “I was sitting on a rock eating lunch and he was like, ‘What are you sitting on the rock for?’ I was like, ‘All right, man. The rock is comfortable.’ He’d just go and grab a chair, pull it over, pull it next to him and his friends. He was like, ‘Come on man, sit, join us.'”

“He was just creating that environment where you were appreciated,” Brown adds of Harmon, 73. “It was something that he did naturally.”

Though their time together was brief, Harmon also imparted some valuable advice on Brown, which he says has stuck with him to this day.

“I remember asking him one time — he’s like, ‘So many people complain about what they do and the hours.’ He’s like, ‘There’s nothing wrong with loving what you do,'” Brown recalls. “And that’s always a bar that just stuck with me and resonated. I was like, oh, you know what? There is nothing wrong with loving what I do. I think I can carry that forward.”

Brown stars as Medwin Harris in Washington Black, which is currently streaming on Hulu, alongside newcomer Ernest Kingsley Jr.

In the period drama, Brown’s character serves as a mentor to Kingsley’s leading character, George Washington “Wash” Black. With Harmon’s advice in mind, Brown made sure to extend their relationship into real life, away from cameras.

“Ernest is an easy person to talk to. Ernest shares himself readily on camera and off camera,” Brown says of their bond in a joint interview with Kingsley. “We would just have little walks between where he lived and where the set was and grab a bite to eat and just chop it up. He’d tell me how his experience was, things that felt good, things that could feel better, et cetera. I would share a little bit about my experience and how I’ve been in similar places, et cetera. But because he had a willingness to share himself with me, I had more than a willingness to share myself with him.”

“I’d agree,” says Kingsley. “I think also it is that willingness to listen as well and to impart knowledge and wisdom and just company. I feel like [he was] wearing two hats, like actor, producer. I guess there’s the worry or concern that, oh, maybe he’s got things to do. He’s got his things he’s got to attend to. Respectfully … you’re a busy guy, but he’s still carved out time for me.”

“He’s still carved out time for so many people on set and just that level of consideration,” he continues. “But it was really easy to build that bond. It just felt so… I had kind of met you before. Kindred spirits, is what you said. It really felt like that, so I was really grateful.”

Kingsley also emphasizes how present Brown was while filming as he praises his costar for the way “he became my mentor” in real life.

“Just him being there, conversations constantly checking in and being like, hey man, you good? How are you finding the experience? So tell me how are you finding things?” he explains of the Paradise star. “It was just having a space where we could just talk and have that kind of friendship and bond.”

“And I want to say mentorship,” he adds. “I think I just asked him so many questions and he became my mentor. And that’s another thing. We still talk, we still message, and I’m just in complete gratitude.”

Based of the book of the same name by Esi Edugyan, Washington Black follows Kingsley’s Wash on his journey after he’s forced to flee his home in Barbados at age 11 due to a death and crosses paths with Brown’s Medwin. The Hulu series also stars Rupert Graves, Edward Bluemel, Tom Ellis, Iola Evans, Sharon Duncan-Brewster and Eddie Karanja.

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Washington Black is streaming on Hulu now.