Suppose you were the last person on Earth, stranded amid the ruins of civilization after a nuclear holocaust, free to infiltrate the houses owned by the dead, even to creep into the Oval Office. That's the vision teased out in the bold but exasperating new play "UpShot," by Israeli American writer Ami Dayan, now at the Church Street Theater.

Produced by the gutsy three-year-old company Forum Theatre & Dance and directed by Shirley Serotsky, "UpShot" launches with a stark image: a black-clad figure standing on a black pedestal, his faced bathed in a harsh white light. This is Man (Jason Lott), a thoughtful, resilient fellow who, in the aftermath of a planet-wide cataclysm, indulges in games of Russian roulette in an empty theatre.

It's a portentous scenario -- but Lott flings himself into the role with such gusto and agility that the narrative acquires a suspenseful urgency. The actor clambers over the pedestal-like cubes that stand about the stage; he stares dazedly into space, face wracked by the sights of the apocalypse; he arcs himself into an agonized backbend that would do credit to Mary Lou Retton.

Unfortunately, Man's mythic adventures -- which include commandeering a BMW, camping out in a cave and ranting at God -- do not constitute the whole plot of "UpShot." Dayan has framed his sci-fi parable with a tedious cliche: a story of a cash-strapped playwright pecking away at a laptop on what he hopes will be a brilliant comic drama. All that end-of-humanity stuff, it turns out, is merely the brainchild of said playwright, John (Scott Graham), who is given to soliloquizing about writing strategies while neglecting his supportive wife, Helen (Adrienne Nelson), and infant son. It will surprise no one that John soon finds himself face to face with his protagonist, Man, allowing "UpShot" to riff simultaneously on the loneliness of writing and the loneliness of existence.

As the piece spirals off into meta realm, borrowing lines from Shakespeare, Chekhov and the Mahabharata, it pauses now and then for tiresome scenes of domestic wrangling. Admittedly, Graham and Nelson are likable and energetic as the conflicted John and Helen, and Nelson also gives pizazz to two subsidiary fantastical characters. Still, by the time Dayan delivers his ending -- which involves eerily applauding ghosts and the legend of Lilith, Adam's first wife -- the narrative feels so contrived that it's hard to care.

A few enjoyable moments do crop up along the way, particularly when Lott holds sway (he does an engagingly arch vaudeville routine) and during the film sequences that burst onto an angled wall. These projections, by Benjamin Flaherty with Paula Gonzalez (video design by Austin Bragg), bear out Forum's declared multidisciplinary focus, and they lend the production an edgy poetry, particularly in the case of a montage that splices landscapes, faces and phone-book listings.

Accommodating these cinematic spurts, David Ghatan's set balances realism and abstraction, with soda cans cluttering up John's desk on the left while the black cube pedestals and angled wall suggest a nihilistic Mondrian. Also striking is Kenneth Gilbert's sound design, which ranges from the "New World" Symphony excerpts mandated by Dayan's script to a hissing wind that makes one long for a parka.

If one occasionally longs for curtain call, too, that doesn't negate the daring of Forum's topically themed "Present Moment" season, which kicked off with "UpShot" and will go on to include plays by Vaclav Havel and the dadaist Tristan Tzara. Perhaps the offerings penned by these famous names will manage "UpShot's" philosophical sweep without its belabored touches.

UpShot, by Ami Dayan. Directed by Shirley Serotsky; scenic design, David Ghatan; costume and property design, Michael Dove; music and sound by Kenneth Gilbert; lighting, Klyph Stanford; original film footage, Benjamin Flaherty with Paula Gonzalez; video design, Austin Bragg. Approximately 90 minutes. At the Church Street Theater, 1742 Church St., NW. Call 202-518-9516 or visit www.forumtheatredance.org.

Existential dramatist: Scott Graham pounds away at the keyboard in Ami Dayan's "UpShot," at Church Street Theater.