Transcript for George Takei on how his childhood imprisonment affected his activism today
This is where we were assembled. And then from here we were sent out to the actual barbed wire concentration camps. Reporter: George Takei is having a flashback to his childhood. But 5-year-old me, I thought it's fun to sleep where the horses sleep. Reporter: Now 82, this is only the second time the actor and activist has been back to the place where he was detained as a child. The Santa Anita racetrack. So you literally slept in the We slept in a stall. Each family was assigned a narrow, smelly stall. It still had the stink of horse manure. And for my parents it was a degrading, painful, humiliating thing. Reporter: Though he's kept his distance physically, that time of his life has never strayed far from his mind, and now he's bringing his experience to a new platform. In his new graphic memoir "They called us enemy," as a way of teaching younger generations a dark chapter in our nation's history. I grew up on comic books, and I thought comic books are what really influences young people, and so let's target youth readership. And they're going to grow up to be people with a knowledge of this chapter of this American history. Reporter: A legend for his role on the cult classic series "Star trek," his recent work an xechx his multifaceted political activism. Takei has xernsd a second renaissance as an outspoken digital provocateur. You have nearly 3 million followers on Twitter. What makes your ideas so young and so appealing to young Well, I try to humanize what I say. Yes, I can be outraged and angry, but I also see the ridiculousness of it. Reporter: One of his most frequent targets, president Donald Trump. Reporter: His former boss on "Celebrity apprentice." You know wholesale has the most respect for you, George? Who is that? Donald Trump. But George, you're fired. Reporter: You referred to him in that tweet as a demagogue. What do you mean by that? He is a man who vilifies and inflikts cruelty. That's a demagogue. Reporter: For Takei it's all an effort to prevent history from repeating itself. This president is someone who doesn't know history, who is reckless, and he is inhuman. At least in our case the children were intact with our families. Reporter: In 1942 as a 5-year-old his family among the nearly 120,000 japanese-americans rounded up and incarcerated after Japan bombed pearl harbor, homes and businesses gone forever. Money was never returned. It was gone. And our home. They took everything. Reporter: As anti-japanese hysteria swept the nation president Roosevelt authorized their forced imprisonment, even those born in the U.S. Like George's mom, here with George and his two siblings. They were locked up behind barbed wire because of their race. And it was executive order 9066, the infamous document. Reporter: The Takei family spent roughly four years incarcerated by the U.S. Government at the Rauer internment camp in Arkansas and tulei lake internment camp in California. And he's outraged that what happened to his family is happening again today. What's happening now on the southern border with people who are fleeing for their lives, we are tearing the children away from those parents and putting them in filthy, disgusting cages with human waste. Reporter: Takei would pursue acting and land the role of a lifetime as the dashing helmsman on "Star trek." Rising from ensign to captain sulu. Don't call me tiny. Reporter: Did you feel pressure to represent, as it were? I was certainly mindful of the role that I'm playing. Reporter: And yet you helped create this iconic character that was strong and sexy and swashbuckling, which really broke a lot of stereotypes in Hollywood. It did. Reporter: That is your most legendary scene, if I may say so myself. After I saw that script, the writer happened to be on the set and I suggested a fencing foil. And he said oh, yeah, that's interesting. Do you fence? And I said, it's my favorite sport. That Saturday I took my first formal fencing lesson at falcon studio on sunset boulevard. Reporter: Takei has a penchant for calling out injustice, using his social media celebrity to build a digital platform, a website, and a podcast, all an extension of his social commentary and activism. Which also fuels his storytelling from the Broadway stage in the 2015 musical "Allegiance." I'll take what chance the future brings Anywhere you go it follow you. Reporter: And now a highly stylized ten-part series on AMC, "The terror infamy." Part Japanese ghost story, part modern American thriller. It's a horror story. And it was horrific for the adults. And a portion of the internees were immigrants from Japan, people who came to this country like all immigrants, with hope and aspirations for a better life. Reporter: But in his graphic memoir Takei confronts these themes head on, depicting his early childhood in the barracks of internment camps, grasping for understanding. Your life story's going to be in every public library. It's kind of humbling. It's a campaign that we've been carrying on for a long time. There are still people that I consider well-informed people. When I tell them about my childhood imprisonment here in America, they're shocked. This is our wedding day. Reporter: George gave us a tour of the home he shares with his husband Brad. We call it team Takei. George and I are a team. Reporter: And after years of fighting for marriage equality, George and the love of his life tied the knot. For 21 years of my life with George as a committed couple, same-sex couple, we didn't really have any legal rights. And so we really were living from the government's eyes as two single men. Once we got married we got all the rights and privileges that come with marriage. And we found out that marriage is really cool. Brad and I were married in the democracy forum because it was democracy that made our marriage possible. Reporter: And that wedding venue, the democracy forum, part of the japanese-american national museum in L.A. That George helped establish. In Arkansas I remember they taught us the pledge of allegiance to the flag in one of those barracks. That was our school. That seems -- And I remember reciting the words "With liberty and justice for all." Innocent child. Totally oblivious of the stinging irony of those words "Liberty and justice for all." Reporter: That's George's kindergarten class taught behind barbed wire. He believes it's a subtle but sinister mistake to call these barracks Japanese internment camps. These are American internment camps, or concentration camps. That's what we were put into. Reporter: His voice still echoing his father, who long ago taught him that democracy is only as strong as the people who take part it. I consider it my responsibility as an American citizen to actively participate, particularly because I know my childhood imprisonment. If we don't educate our fellow Americans to the vulnerability of our democracy, how fragile it can be, then we're not being responsible citizens.
This transcript has been automatically generated and may not be 100% accurate.