Amanda Schoonover and Kirsten Quinn in Betty’s Summer Vacation at IRC. (Photo by Johanna Austin / AustinArt)

When I was growing up, a weekly TV treat was The Wonderful World of Disney, which began with a song full of hope: “The world is a carousel of color / Wonderful, wonderful color.”

I thought of that show as I watched the opening of Betty’s Summer Vacation, where the title character and her friend Trudy plan their idyllic summer. The two are situated in a sea-side cottage practically vibrating with cheerful pastels (Dirk Durosette did the dynamite set), and they’re dressed for fun (great costumes by Millie Hiibel). What could possibly go wrong?

Well, quite a lot, really. First, the two don’t seem ideally paired. Betty (played by Kirsten Quinn) is gorgeous, but rather tightly-wound and controlling. Trudy (Amanda Schoonover) is adorable, but motor-mouthed and filter-less. Minutes later, a shy, clean-cut young man named Keith (Anthony Crosby, sweetly droll) arrives, clutching a hat box. Surely, it doesn’t contain a severed head… or does it?

Oh, and then there’s Trudy’s overbearing mother, Mrs. Seizmagraff (the great Tina Brock) who seems like a cross between Lucy Ricardo and Norma Desmond, and insists on reminding her daughter what a constant disappointment she is. And Buck (Chris Fluck), an aging surfer with (as he imagines it) an irresistible allure for the ladies—the kind of guy who thinks a good come-on line is: “I have pictures of my penis; do you want to see them?”

Still, Betty’s Summer Vacation is a comedy… isn’t it? For heaven’s sake, there’s even a laugh track: unseen voices cackle at every joke, often disconcerting Betty and company.

But this is a play by Christopher Durang, so of course the palette is loaded with darker shades. Those ghost-gigglers seem to chortle even harder at moments that are sad, painful, and scary. These include a fatal car accident, tales of incest-rape, and severed male genitalia that ends up in the freezer. Horrifyingly, one character might be a serial killer; worse, another actually likes David Mamet’s Oleanna.

Kirsten Quinn in Betty’s Summer Vacation at IRC. (Photo by Johanna Austin / AustinArt)

There is a point to all this, but it doesn’t become clear till quite late in the action—and I shouldn’t give away too much. But consider that the presence of an increasingly demanding, unruly audience suggests the relationship of a playwright and his public is something close to mortal combat.

This is a lot of territory to cover in an 85-minute play, and it takes the audience on a wildly unpredictable ride. Fortunately, Brock (who also directs) is both a devotee of absurdism and a demonstrated master at negotiating tonally complex, off-center works—skills that are very welcome here.

For my taste, this production—by Brock’s estimable company, the Idiopathic Ridiculopathy Consortium—is a bit more cranked-up than necessary. I’d like to see more of the collision between sitcom gloss and Hitchcockian gloom; the pace is sometimes so antic that the jokes (often barbed and multi-layered) don’t quite have time to land.

But much of the show is comic bliss, not least in the sheer exhilaration we feel watching three of Philadelphia’s best actresses giving gloriously unbuttoned, wickedly funny performances. Brock, Quinn, and Schoonover (the order here is strictly alphabetical) have rarely looked more joyful onstage. It’s as though they’re having the time of their lives up there—and how could the audience feel otherwise?

Betty’s Summer Vacation plays through June 30^that the Walnut Street Theatre / Independence Studio on 3. For more information, visit the Idiopathic Ridiculopathy Consortium website.