Stephen Moyer, appearing in ‘Chicago,’ has theater in his blood

In the exclusive club of television stars who are also bona fide musical theater veterans, actors Neil Patrick Harris and Matthew Morrison seem to get all the attention. But Stephen Moyer of “True Blood” has the lung power and the agile feet to merit consideration for a lifetime membership.

Long before he landed the role of glowering vampire Bill Compton in the popular HBO series, Moyer paid his dues as a theater workhorse in his native England, appearing in his first shows as a preteen before graduating to roles in big London productions.

On Friday, Moyer will take the stage for the first time since he left the theater 18 years ago to pursue his screen career. The 43-year-old actor is starring in “Chicago” at the Hollywood Bowl, where he will play the slick lawyer Billy Flynn opposite celebrity hyphenate Ashlee Simpson as Roxie and musical actress Samantha Barks as Velma.

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Over a hasty breakfast consisting of an egg sandwich and coffee before rehearsals on Tuesday, Moyer described himself as terrified about performing in front of nearly 18,000 people a night for three nights.

“It’s been awhile since I’ve had to retain so much dialogue,” he said, but added that he’s been “pleased at how quickly it’s all come back to me.”

Moyer said he came to “Chicago” rehearsals almost directly from shooting the sixth season of “True Blood” on a nighttime schedule. He’s had to cram for the musical, learning most of the part during the production’s 10-day rehearsal schedule.

But Moyer isn’t a complainer and showed no sign of fatigue. Twice during the interview, he jumped out of his seat so that he could work on a scene with costar Drew Carey, who plays Amos Hart and was rehearsing down the hall.

“We haven’t had much time to rehearse actual dialogue. It’s been a lot of running though the show. I like working on actual scenes,” Moyer explained after apologizing for the interruptions.

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A gregarious interview subject, he became particularly animated when the conversation turned to his days toiling away in British theater. By his count, he had performed in more than 60 musicals by age 18.

His first musical after graduating from drama school was “Oliver!” in the part of Noah Claypole. He later appeared in Pete Townshend’s rock opera “The Iron Man” at the Young Vic in London.

A desire to diversify eventually led him to the classics. Moyer recalled a 1995 tour of “Romeo and Juliet” — in which he played Shakespeare’s tragic hero — that traveled to Japan. During one performance, he experienced an actor’s worst nightmare.

“I was in the middle of my favorite speech and I just blanked,” he recalled. He ended up skipping most of the soliloquy by calling out to an offstage character who barely had time to get dressed.

By the end of that tour, “I needed a bit of a break [from the stage]. But I never intended it to be 18 years,” Moyer said.

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The idea to cast Moyer in “Chicago” came from conductor Rob Fisher, who led the 1996 Broadway revival and will conduct the show at the Bowl.

Fisher said he saw a YouTube clip of Moyer singing “Hard Hearted Hannah” in a Season 2 episode of “True Blood” and thought he would make an ideal Billy Flynn.

“I thought his skill level was perfect for the role, and it was auspicious that he was singing ‘Hard Hearted Hannah,’ which is from the same time period as ‘Chicago,’” said Fisher.

A later meeting with actress Brooke Shields, who is directing the Bowl production, clinched the deal for the actor.

Moyer’s stage talents have surprised some of his fellow cast members. “I didn’t know that he could sing. I mean, I’d heard it through the grapevine, but I had no idea how good he is,” said Barks during a rehearsal break.

The 22-year-old British actress, who has performed on the London stage and played Eponine in last year’s movie version of “Les Misérables,” described Moyer as a down-to-earth performer and doting father. “He’s brought his kids to rehearsals. It was quite charming, actually.”

Although Moyer’s publicist warned against asking personal questions, the actor was happy to chat away about his home life with his wife and “True Blood” costar, Anna Paquin. For the past few days, he’s had to play Mr. Mom to his four children at their Venice home while Paquin was traveling for work.

The actor said his 10-month-old twins with Paquin are at the age where they’ve become fascinated with electrical sockets. “Any open hole in the wall and they go right toward it,” he said. (His two older children are from previous relationships.)

After “Chicago,” he said, the family will take a long vacation in London, where among other things he plans on catching up on some theater.

Moyer said his dream stage job would be repertory productions of the musicals “Sweeney Todd” and “La Cage aux Folles.” He appeared in “Sweeney” a few times in England but never in the lead role. For “La Cage,” he said he wants to play the role of cross-dressing performer Albin, whose drag name is Zaza.

“You really have to be 50, I think, to play him properly. And I’m not quite there yet,” he said with a wink.

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“Chicago: the Musical”

Where: Hollywood Bowl, 2301 N. Highland Ave., Los Angeles

When: 8 p.m. Friday and Saturday, 7:30 p.m. Sunday

Price: $12 to $134

Contact: (323) 850-2000 or (800) 745-3000