For someone who got into musical theater by accident, Justin Gray has made a pretty nice career of it.

The music director for the last 13 years at the Welk Resort Theatre north of Escondido, he's also producing his own musical, "Company B," at the California Center for the Arts, Escondido, tonight through Saturday.

Gray, who grew up in Valley Center and lives in Escondido, described "Company B" as "an original musical that I wrote 10 years ago. It was produced before, in Old Town, outside. We did it three years in a row, and then gave it a break.

"I've always wanted to do it indoors on a large-scale basis, so we've hired a professional director, and we've got Dave Humphrey, an Equity actor, playing the lead."

The rest of the roughly 60-member cast is volunteer, he said, and there is a 10-piece band.

"It really is a huge production."

The musical tells the story of the legendary Mormon Battalion's 1846-47 transcontinental march -- a monument to which sits in Presidio Park in San Diego, on the hill above Old Town near the original site of the old Spanish mission (which was later moved by the Spanish to its present location in Mission Valley).

"It tells the story of the Mormon Battalion's infantry march, the longest infantry march in U.S. history, 2,000 miles from Iowa to San Diego," Gray said. "Five hundred men went to assist with the Mexican-American War, but by the time they got to San Diego, the war was over."

Besides working on "Company B" when interviewed in late June, Gray was also in rehearsals for the then-pending opening of the Welk's current show, "Buddy, the Buddy Holly Story."

"We have to overlap" current shows with rehearsals for the next shows, Gray said of the Buddy Holly rehearsals going on in the afternoon before the evening's presentation of "I Left My Heart," a since-closed musical revue celebrating the music of Tony Bennett.

"There's never a time we don't have a performance, so the last 10 days of a show, we start rehearsing for the next show."

That lack of a break in the Welk performance schedule has led to some pretty impressive numbers in Gray's career.

"I've been involved in every single production since (1993)," he said. "I play in every show except when I'm able to carve out vacation time. I've been in 400 performances a year for 13 years -- something like 5,000 performances here."

Like many kids, Gray was introduced to music with piano lessons -- in his case, from his father. But his initial introduction to the piano didn't include any lessons in reading music.

"I played by ear for many, many years. In my teenage years, I played by ear very well but my reading was very poor. I knew if I wanted to become a successful musician, I needed to be proficient in both. So I worked very hard to improve my sight-reading skills. Now, as a professional, I find that having both sight-reading skills and improvisational skills really helps me in my job."

He attended San Diego State University in the 1980s, and while he was studying music he wasn't sure what he was going to do after graduation.

"When I went to San Diego State, a position opened up there for the drama staff accompanist. That's when I really got heavily involved in musical theater. And I actually worked there while I was working on my master's. From there, I went to Starlight Theater and was the musical coordinator for a number of years, and then went to Welk.

"I feel very blessed," Gray said of his full-time job at Welk.

While he said he has missed out on being part of the live music scene in San Diego County, he knows he's been fortunate to find the kind of stability most musicians can only dream about.

"I'm very lucky to have a full-time paycheck with benefits. It doesn't get stale because I do a show for seven to 10 weeks, and then do a new one. It's always exciting, always something new going on.

"In addition to that, at home I have a recording studio where I create soundtracks for high schools and small theaters across the Western United States. It's for those with not enough money for a full orchestra, but wanting more than a simple piano, so they're willing to use a recording."

And while working in the theater often means working nights and weekends, Gray said the Welk schedule isn't quite as onerous on family life as at many other theaters.

"What's nice with the Welk schedule, Friday nights are usually off. The Friday nights were never well attended, so they canceled those and added a Saturday matinee.

"Now we can go to Cruisin' Grand (in Escondido) or see a show."

And after "Company B" closes, Gray is taking one of those aforementioned breaks. He won't be performing in the Buddy Holly show at the Welk, although he did put together the arrangements and helped run the rehearsals.

"I'm taking four weeks off to do 'Company B' and then go on my own personal vacation."

"Company B"

When: 8 p.m. today through Saturday; 2 p.m. Saturday

Where: California Center for the Arts, Escondido, 340 N. Escondido Blvd., Escondido

Tickets: $9.50, general; $8.50, seniors, military, students with ID and children 11 and under

Info: (800) 988-4253