On the show, which wraps its third season Wednesday night at 10, Charles Esten plays Deacon Claybourne, a ruggedly handsome Music City veteran involved in a complicated relationship with the town's reigning diva, Rayna Jaymes (played by Connie Britton). Viewers are accustomed to watching Claybourne perform in the musical numbers that pepper each episode.
But on Saturday night the man with the 5 o'clock shadow wasn't singing on screen — he was doing it on the stage of the Nokia Theatre in downtown Los Angeles. What's more, he wasn't going by Deacon but by his real-world nickname, Chip. The well-attended gig was part of a U.S. tour featuring Esten and a handful of other "Nashville" stars, including Chris Carmack, who plays bro-country hunk Will Lexington, and Clare Bowen, known on the show as the sensitive Scarlett O'Connor.
The idea? To promote the series, of course, but also to shed some light on the people behind the characters.
"I don't feel as though it's Deacon out there at all," Esten said before Saturday's show. "Perhaps that's who the audience is seeing. But I wouldn't know how to go out there without a script and act like Deacon. I can just be me." Still, he admitted with a laugh, he can understand any confusion.
"For one leg of the tour, a couple of us were on a chartered jet, and as I got on there, I kept expecting Juliette Barnes to walk on and make me get out of her seat," he said, referring to "Nashville's" domineering young singer played by Hayden Panettiere. "There's definitely a blurred line between fiction and nonfiction."
And there's little reason to unblur it. Renewed last week for a fourth season, "Nashville" — which averages about 5 million viewers per episode — has spawned a series of successful companion albums, including the latest, which came out Tuesday and immediately shot to the upper reaches of the iTunes country chart.
Songs on the albums are credited to the actors, many of whom worked as musicians before joining the show. But following the recent No. 1 debut by the soundtrack to Fox's smash "Empire," the steady stream of "Nashville" content suggests there's a healthy market for music that sits at the intersection of fantasy and reality.
Dawn Soler, ABC's music chief, said the demand recalls the craze for movie soundtracks in the 1980s and '90s, when the likes of "Footloose" and "The Bodyguard" spun off discs that sold millions.
"But to see it come back in a different way through television is really exciting," Soler said. "With film, the soundtrack is a way to relive the experience of the movie, whereas with TV it's a longer relationship. You can build a lifetime love affair."
Crucial to that sustained interest is the believability of the show's performances, said Frankie Pine, who as "Nashville's" music supervisor is in charge of selecting songs for the characters to sing.
"We want everything to feel incredibly real, whether it's a concert scene or a scene in a recording session," Pine said.
That's partly why the series recruited Buddy Miller, widely respected for his work with artists such as Emmylou Harris and Willie Nelson, to serve as music producer. Like Timbaland, who handles the music on "Empire," Miller knows what sounds credible — and how to execute it properly.
Yet maintaining that believability in person, away from the controls available in the recording studio and the soundstage, is a different matter.
Gathered with his cast mates backstage at the Nokia, Carmack said it was precisely the experience of filming the series — which shoots in Nashville and uses many of the city's most recognizable venues — that bolstered his abilities as a live performer.
"I was writing songs and playing empty bars in Los Angeles for years," he said. As Will Lexington, though, he's been performing in giant arenas. "And the whole time [on set] I had a director going, 'That looks good — do more of that!'"
Esten agreed, noting that he filmed scenes at the Grand Ole Opry and the Bluebird Cafe prior to playing real gigs in those rooms. "By that point I felt like I'd been there," he said.
Sam Palladio, who plays the moody Gunnar Scott, said working on set was educational in more practical ways too: He'd never used an in-ear monitor, which helps a performer hear his accompaniment onstage, until he shot a scene in which Gunnar learned how to use the device. Now, on tour, he relies on one every night.
"It's all very meta," said Aubrey Peeples, known as Layla Grant on the show.
So far, all that experience appears to be paying off. At last month's Stagecoach festival in Indio, Esten, Carmack and Bowen were invited to play on a bill with superstars like Tim McGraw and Miranda Lambert, an indication that the country music establishment is taking "Nashville" seriously (or at least it believes the show's fans are).
And Saturday's concert felt assured enough as each of the performers complemented tunes from the show with smartly selected covers and sturdy originals of their own. One especially powerful song, "Heart on Fire" — sung by Lennon Stella, who plays one of Rayna's daughters on TV — could've easily passed for early Taylor Swift.
Sharing anecdotes about the years he'd spent as an actor in L.A., Esten seemed the most determined to make a mark apart from his character; he even opened his set with a song he'd written himself, called "Whiskey Lips."
Was he sending a message to the Deacon Claybourne lovers in the house? Perhaps. But nobody needed to worry. There in the Nokia's lobby sat a pile of T-shirts for sale, each emblazoned with the words "Team Deacon" across the chest.
When: 10 p.m. Wednesday
Rating: TV-PG (may be unsuitable for young children)