If Pittsburgh’s incarnation of the nationally popular storytelling series keeps growing like this, we’ll have to start calling it “Mothra.”

The past few summers, the Moth Mainstage program filled the 500-seat New Hazlett Theater. But in this, its fifthl appearance, the annual show made the big leap to the Byham with seemingly little trouble, selling all but a handful of the Downtown venue’s 1,300 seats.

Those seat-holders were treated to a fine show, courtesy of the New York-based Moth organization, local Moth partner Pittsburgh Arts & Lectures and the Pittsburgh Cultural Trust.

As usual, the Mainstage show matched local and visiting talent. Chicago-based teller Shannon Cason told a riveting story of how a bank-manager job he had as a young man collided with his gambling problem. And New Yorker Trisha Coburn offered a dazzlingly detailed account of how a 1960s-era charm school changed her life as a small-town Alabama girl on welfare.

Local performers included Kelly Flanagan Dee, who produces Pittsburgh’s monthly Moth StorySLAM, at the Rex Theater, and who told of trying to relate to sketchy South Side neighbors as a younger woman.

Two other Pittsburgh-based tellers were among the evening’s biggest hits. Justin Strong, who founded the recently shuttered East Liberty cultural landmark the Shadow Lounge, told how the venue came to be — it was the next step from the parties he held in his off-campus house as a Pitt student — and its precarious early days, long before anybody was bothering to gentrify 'Sliberty.

The story included a tibdbit Strong later confirmed he’d never mentioned publicly before: how, in 2002, with the Lounge about to lose its lease, neighboring East Liberty Presbyterian Church stepped in with cash assistance and other behind-the-scenes help. The Lounge lasted another 11 years.

The evening’s closer, and the only national celebrity on the bill, was David Newell. The actor better known as speedy-deliveryman Mr. McFeely, on Mr. Rogers’ Neighborhood, told how he got into acting — a charming anecdote about seeing his first play at age 8, a production of Harvey starring Joe E. Brown, at Downtown’s old Nixon Theater. (This was in the mid-1940s, shortly before the grand old theater was demolished.)

Newell’s story, a heartwarming tribute to Fred Rogers and his long-running show, included an anecdote set in 1982, in NBC headquarters, in New York. (Rogers was there to guest on Letterman — with Julie Andrews and Andy Kaufman!) At the encouragement of an NBC staffer, Newell accompanied Rogers to the dressing room of Eddie Murphy, whose spoof “Mr. Robinson’s Neighborhood” was then a recurring skit on Saturday Night Live. (The summit ended in a hug.) Cute stuff.