Promotional image for, “Giant Box of Porn” at the Capital Fringe Festival. (Field Trip Theatre)

It is a truth universally acknowledged that a married man in possession of a giant box of pornographic videotapes may encounter trouble with his wife.

In the Capital Fringe Festival comic drama “Giant Box of Porn,” now playing to sellout audiences at the Warehouse, a giant box of porn mysteriously pops up in the small apartment living room of young marrieds Kate and Ron. Like the monolith in “2001: A Space Odyssey,” the imposing hoard of smut poses deep questions: How did it get here? What does it mean?

Kate wants it all hustled out. Ron wants to solve the unexpected riddle. He catalogues the collection. He stacks the cassettes just so on the floor, making his own little Easter Island of the tapes. When his dim friend Sherlock picks up a VCR from a thrift store, Ron’s in business: He can watch ’em.

The nicely surprising script is by Patrick Flynn, and it gets the audience into a pleasant laughing rhythm for its first 45 minutes. Then the 90-minute play loses stamina and inventiveness for a while, merely going through the motions of what settles into a standard relationship drama. The professionally intimidating Kate and the boyish Ron, it seems, want very different things.

Flynn’s D.C.-set, four-character script rediscovers its mojo toward the end, and the production by the new Field Trip Theatre is consistently acted with brisk humor. Anna Jackson is a tart Kate, nicely clipping off barbs at Grant Cloyd’s generally bewildered Ron. As Kate’s sister Vanessa, Morganne Davies is amusingly open to the implications of the sex tape stockpile, and Will Hayes wins a lot of laughs as the strangely skittish Sherlock — and not just when he makes a late entrance in a cheeky costume too unexpected to spoil here.

The show is more demure than the title suggests, even with moanin’-groanin’ sound effects as Kate and Ron finally watch a tape together. Director Maureen Monterubio’s staging is admirably direct and never forced. As its chirpily funny start sobers into earnestness, “Porn” keeps its pants on.

Giant Box of Porn

By Patrick Flynn. Directed by Maureen Monterubio. 9 p.m. Tuesday and 6 p.m. Sunday at the Warehouse, 645 New York Ave. NW. About 90 minutes. $17, plus the one-time purchase of a $7 festival button. Visit