1_T3_LUTS_Top-Bottom_Bob Hess_Jessica Cavanagh_David Coffee_Lydia Mackay_Photo by Stephanie Drenka

Hess, Cavanaugh, Coffee and Mackay play up the comedy in ‘Light Up the Sky’

Post-modernism has made it all but impossible to enjoy certain mid-century comedies anymore. Audiences are savvy now — they carry irony with them like rosaries at a convent. At times, it’s more of an impediment than it should be, as with Light Up the Sky, the Moss Hart-written play now at Theatre 3.

The premise is pure Inside Showbiz: A new play is getting its first out-of-town tryout in Boston and all those who’ve read it agree it’s a work of genius on par with Aristotles Poetics. At least until opening night, when walkouts, titters and the opinions of the producer (David Coffee), star’s mom (Ivy Opdyke) and even a rival playwright (Doug Fowler) proclaim it an allegorical disaster. That’s when the star (Lydia Mackay), producer and director (Bob Hess) start blaming each other, and especially the playwright (Seth Monhollon), for saddling them with a bomb.

The leading roles are as impeccably performed as the script allows. Hess received an ovation for his entrance before delivering a line of dialogue, coming at us with more camp than a Boy Scout Jamboree. Coffee’s blustery slow-burning mogul and Mackay’s cryptic diva banter like The Honeymooners. Opdyke’s droll, drunken sass and Jessica Cavanaugh’s charm add fine support.

But the script is its own distraction. We know too much now about how the business — and art — of the stage really work; musicals like The Producers and Curtains are set in basically the same era, but written with a contemporary eye that let’s you know they’re in on the joke. Not so here, where the very conceit of the plot is hard to swallow. The dialogue is frequently clunky and painfully expositional; Monhollon and Fowler in particular are sentenced to speak Hart’s Big Pronouncements about The Theatuh. That’s a big hurdle to clear, but this cast does its game best.

Theatre 3, 2900 Routh St. Through April 3.