CHICAGO — Nursing a sore throat and a depleted voice, Charlie Barnett leans against a door frame surveying the action before him.
A wardrobe assistant adjusts the line of the fleece hoodie he wears as he stands on the edge of what looks like a fire station squad room. He and his colleagues are awaiting word from the chief about the condition of a fellow firefighter.
See a gallery of images from "Chicago Fire" and its set.
After the update, the crew starts to banter. Voices are raised and taunting ensues. For a change, it's not directed at the rookie firefighter Barnett plays on the NBC drama "Chicago Fire."
Barnett's character, Peter Mills, watches from the sidelines, a little wary of how things could shift but not wanting to miss a minute of what's happening.
Barnett himself is hardly staying on the sidelines. He is relishing every moment of his first primetime series and his time on the set of "Chicago Fire," which may have attracted enough of an audience at 10 p.m. Wednesdays to earn a full-season pickup. On Dec. 5, with no "CSI" competition, the show had its highest ratings of the season.
The series is a breakthrough and the biggest boost yet to the 24-year-old actor's career, which began at age 7 on stages in and around Sarasota.
Playing Peter Mills, the rookie candidate, in Station 51, could make him a star or at least a recognizable performer, which would likely lead to more work.
Barnett has found a home in Chicago with a lot of nearby friends from his days as a student in Booker High School's Visual and Performing Arts Center.
But for now, he's focused on the long hours on the set and locations around Chicago.
Behind the scenes
In what looks like a factory warehouse on the outside, designers have created Station 51, home to a fire unit led by actor Jesse Spencer and a rescue squad led by Taylor Kinney. Each team battles for prominence after the latest accident, explosion or fire.
The set resembles an actual station house, if it were missing ceilings and walls and had a lot of extra lights and cameras around.
During filming of the squad room scene, two surrounding hallways are filled with assistants, wardrobe, makeup and hair specialists and many others making sure each shot matches the last.
Around the corner is a break room and stationhouse kitchen where Barnett's character has been doing a lot of cooking.
Co-stars and crew members smile warmly as he walks by or stop for a quick hug, while he gives a visitor a tour of the facilities, posing for pictures by one of the firetrucks inside the studio.
Outside a prefab wall and door is an empty warehouse, where other crew members create props and special effects. An empty area beyond held the soundstages for Kelsey Grammer's series "Boss," which was canceled.
The essence of Barnett's character was established in the pilot, which was filmed last March and aired as the first episode in October. Peter is the new guy in the station house but he comes from a firefighting family.
Unlike the many roles he's played on stage — where the lines and situations are the same every night — each time he gets a new "Chicago Fire" script, he learns something new about Peter and his background. For example, one week he learned that in his off hours, Peter works at the diner owned by his family. He knows how to cook and becomes a station house chef.
There have been subtle changes or developments in Peter's life each week, but Barnett said his training at Booker High in Sarasota and at the Juilliard School of Drama helped him develop skills to build his characters so he can adapt to each new piece of information.
"The hard part is creating layers, doing your work, and then when you get to the room for a scene, it should be off your shoulders. It's just something new for the character to deal with," Barnett says.
"Every time we get a new script you have things you'd never thought would happen, so I try to do an incredible, deep-layered backbone. Of course, things change and there's an ebb and flow, but all these things only solidify it for me. When I'm filming a scene with Jesse or Eamonn (Walker, who plays the station chief), I don't want to think of any of that stuff in my head. I just want to enjoy myself. It's work meets life."
As in real life, Peter faces things he's not always prepared to deal with or see. In a recent episode (aired Dec. 5), he became overwhelmed after a train accident.
"I see some pretty horrific stuff that no firefighter ever wants to deal with," he said. "It kind of knocks me off my base. Peter Mills is really passionate about his work, serious about it. He comes from a line of men that were firefighters. There's an honor of continuing this line and say 'Yes, I can be the best at it.' That episode was the first time I was really thrown off my base and wondering can I be this strong personally? That's something I've faced in the last few weeks. It's interesting how your characters mesh with your personality."
The advantages of being an unknown
Joe Chapelle, one of the show's producers and an occasional director, said he's impressed with Barnett, whom he first met on the show's second episode.
"I met him and talked to him and to see him work on set, I'd thought he'd worked in front of the camera for years," Chappelle said. "I found out after the fact that he hasn't done much on-camera work. You'd never know that."
Prior to "Chicago" Fire," Barnett played a charming rapist in "Law & Order: Special Victims Unit" — his character, curiously, was named Chuck Mills — and he was seen in an episode of "Law & Order: Criminal Intent." Both shows were created by "Chicago Fire" executive producer Dick Wolf.
Barnett also had a small role in "Men in Black 3," and roles in several independent films, including the comedy "Gayby," which was shown at this year's Sarasota Film Festival and released on DVD this month.
Being something of an unknown is an asset to his role in "Chicago Fire," Chappelle said.
"The audience has no preconceptions about him and the character he plays. When you don't have those preconceptions, you don't know where the character is going," he said.
But Chappelle clearly sees big things for the young actor.
"He's so likable. He has an earthiness about him. He's charismatic and that translates very well and I think people love watching him. I think what he's doing with Peter Mills will define his career persona for the rest of his life. He's a good guy, like a Matt Damon kind of guy or even Tom Hanks.
Barnett has a special love for theater and wants to keep it part of his career "but they don't pay like this. Theater can keep you alive to a certain extent, but it can't keep your family. It can't keep you traveling. I want to work on something I enjoy that I feel is creative."
If the series survives, Barnett can get his summers off to pursue other projects. And there are a lot of possibilities out there, he said.
Since moving to Chicago, he has been surrounded by old school friends. "There are about 20 of us living here now. It's a great town to be in," he said.
And he has been making friends with his castmates.
"There haven't been any diva moments. No one is flipping out or being rude to the cast and crew. I've heard stories from some of these people about their experiences on other sets and compared to this, it sounds like we're in heaven."