This period of American history is not as widely known as nobler aspects of the war years. For the actor, it is anything but obscure, anything but excusable.

"When Pearl Harbor was bombed, Japanese-Americans, like every one else, rushed to enlist," he says, "but they were denied and labeled enemy non-aliens. That's citizenship in the negative."

With his parents and siblings, Takei was first sent to a camp in a swampy part of Arkansas, then to another in an isolated section of Northern California.

Partway through the war, when more manpower was needed for the armed services, the confined Japanese-Americans were given a questionnaire to fill out.

"Everyone in the camps over the age of 17," Takei says, "including an 87-year-old lady, was first asked, 'Will you bear arms to defend the United States of America?' The second question had two parts: 'Will you swear loyalty to the United States of America and forswear your loyalty to the emperor of Japan?' It was outrageous. If you said yes, you were fessing up to having been loyal to the emperor."

That question shook up the community.

"Some bit the bullet and answered yes," he says. "Some, like my parents, answered no. My father said, 'They took my home, my business. I'm not going to let them take my dignity.' That's the story we tell in the musical 'Allegiance.' It's about allegiance to your family and, ultimately, to yourself."

That musical came about serendipitously.

A few years ago, Takei and his husband attended a play in New York. Two strangers in the next row, Jay Kuo and Lorenzo Thione, recognized Takei's voice and struck up a conversation. The next night, the four men happened to be at another theater for the hit musical "In the Heights."

"At the end of Act 1, the father in the story sings about how he can't afford to send his daughter to college, which makes him feel completely useless," Takei says. "That struck a chord and reminded me of my father's anger in Arkansas, how he wanted to do more for his children. At intermission, Jay and Lorenzo saw me trying to dry my eyes and asked me why it had affected me so deeply."

Over drinks after the show, Takei told the two men about his years in the camps. Kuo, who had written a few musicals, and Thione, an entrepreneur, suggested that Takei's experiences would make a great subject for a musical. Kuo soon composed a song and emailed a clip of it to Takei to give him an idea of what the musical could be like. The song was called "Allegiance."

"It really captured the anguish of a Japanese-American father in an internment camp," Takei says. "There I was at my computer, bawling away listening to it. So I wrote Jay back and told him, 'Let's do this.' "

In short order, Kuo finished all the music and lyrics for the show; he and Thione wrote the first draft of the book. The project was picked up by the Old Globe in San Diego, one of the country's leading regional theaters, with a strong record of sending shows to Broadway. The company brought in Marc Acito to help with rewrites of the book.

"Each tweak made it stronger," Takei says.

Takei was given a major role in the show, portraying a survivor of the camps who looks back on those years. The actor had another major role, too, offstage — finding backers for the musical. As part of his fundraising efforts, Takei gave several readings of the work for Japanese-Americans and discovered that the past was very much in the present for many of them.

"The [loyalty questionnaire] had fractured the Japanese-American community, and that fracture reappeared at those investor meetings," Takei says. "People were wagging fingers at each other afterward, saying things like, 'You killed my mother.' It was shocking to me. It was 70 years after the war, but the wounds were still there; the scabs were taken off."

"Allegiance" had its premiere in 2012 and became "the highest-grossing show in our 75-plus-year history," says Eric Louie, associate producer at the Old Globe.

The process of getting the musical to the stage was a smooth one.

"George is the nicest human being you'll ever meet in your life," Louie says, "and one of the most eloquent speakers you'll ever hear. There's a real power in listening to George. He really led the charge for 'Allegiance' and opened people's eyes. You could not help but get on board. We all felt this was a story that needed to be told, a relevant and important story that does not get enough attention."

After the success of "Allegiance" at the Old Globe box office and with the local press, Takei and the show's creative team were ready to conquer Broadway.