Real-life tragedy figures heavily among the stories told by this year’s lead actor Emmy nominees, especially for actors seeking to capture characters based on real people.

Jharrel Jerome, for example, is nominated in the lead limited series/TV movie actor category for playing both the younger and older versions of Korey Wise in Netflix’s “When They See Us,” whose wrongful conviction as one of the Central Park Five led to years in prison.

Researching the role was difficult because, in trying to understand the differences between Wise before and after incarceration, Jerome didn’t have anything to reference about Wise as a young teenager. Thus, he says, his conversations with Wise were not much at all about “his tragedies. Instead, we talked about what he loves to do, who he loves.” That helped him come to understand the “16-year-old boy that’s still trapped inside of him. To see that life inside him today is how I channeled into the young Korey.”

“When They See Us” was Jerome’s first time playing a role that would haunt him after he left the set. But spending time with the real Wise was “pretty much all the therapy and the medicine I needed for this process, to realize I’m doing this for a beautiful purpose — not just to share a story of sadness and a story of pain; it’s also a story of triumph and overcoming.”

Also nominated in the lead limited series/TV movie actor category is Jared Harris, who stars in HBO’s “Chernobyl” as the real-life Valery Legasov, who was tasked with investigating the catastrophic 1986 nuclear explosion. In playing the character, Harris had the advantage of being able to draw on elements of historical fact known about the man, but because he is a far less famous figure than Harris’ previous roles (such as Andy Warhol or King George IV), he was able to remain focused on this specific version of the man.

“It was one of the first times that I had done a lot of research on a character that turned out to not be particularly useful,” he says. “After a while, I just really decided to rely on the script.”

What Harris says he found most interesting about the character was “that he never expected to wake up and have to make those kind of choices. He was a reluctant hero — I liked the idea that he was afraid.”

Lead limited series/TV movie actor nominee Benicio Del Toro, however, relied heavily on research to make sure he never forgot that he was playing a character “who deals in pure evil” in Showtime’s “Escape at Dannemora.” His Richard Matt was a convicted murderer who seduced a prison worker and planned an escape from the Clinton Correctional Facility in 2015. While Del Toro enjoyed getting to show a human side to the man, he notes it was always important for him to remember that it was still “not the good side necessarily.”

Meanwhile, Milo Ventimiglia received his third consecutive Emmy nomination in the lead drama actor category for NBC’s “This Is Us.” This season, much of his storyline revolved on his character Jack’s experience in the Vietnam War. Ventimiglia says he didn’t do a lot of research on the conflict, because most of those who served in Vietnam “didn’t know about the war. They didn’t know why they were there.” But he did speak to his father, a two-tour veteran, about his experiences. His father helped him understand his matter-of-fact attitude toward the service: “My dad just says, ‘Oh, yeah, I was in Vietnam. And then it ended and then I came home.’ Much like Jack.”

However, that doesn’t mean his dad — or by extension, Jack — was unaffected by the experience. “War changes us as individuals,” Ventimiglia says. “I couldn’t even imagine the deep wounds and scars that are inside an actual soldier.”