Credit: Peter Cunningham

It was a balmy Friday evening in midtown Manhattan when The Lifespan of a Fact began previews; the gilded theater was only half full. Or maybe it was Saturday, with a little chill in the air and a crowd at capacity. Does it really matter exactly what the details were?

It does very much, actually — at least to Daniel Radcliffe’s Jim, a fact checker at an unnamed prestige publication assigned do a final read on a piece by John (Bobby Cannavale), a star journalist whose gift for full-color storytelling may not be matched by his strict adherence to fact.

The action is brisk (only 85 minutes, without intermission) but the morality is muddled in the new drama from Jeremy Kareken, David Murrel, and Gordon Farrell, based on a 2012 accounting of the incident by its two real-life protagonists, John D’Agata and Jim Fingal.

Some things seem indisputable: A 16-year-old boy named Levi Presley is dead, after jumping from the observation deck of Las Vegas’ Stratosphere Hotel and Casino. But whether the deck stood at 1,149 feet, and whether it all synced up with other local phenomena that day (including but not limited to banned lap dances, the world’s oldest Tabasco bottle, and a tic-tac-toe-playing chicken named Ginger) is for Jim to verify, or not. And also for his editor, Emily Penrose (Cherry Jones) to supervise.

The idea of subjective truth in journalism — or anywhere, really — has an obvious timeliness in our era of alternative facts, and Lifespan does offer an intriguing story, and three fine, famous actors to play it. But the outcome never feels quite as consequential as it should, possibly because it isn’t actually that ambiguous; John tells unnecessary lies under the guise of artistic license, and Jim is left to be the didactic classroom-pet nag, asking why the article can’t just go with the actual 31 strip clubs licensed in the city, instead of 34. (Is John a secret numerologist or something? It’s hard to know otherwise why it matters so much to tell that particular lie.)

The part of Emily, which should be catnip to a stage veteran like Jones, also feels oddly underwritten, both as character in a play that only contains three of them, and as an actual editor following the generally accepted guidelines of good journalism.

There is plenty of sharp repartee, though, and few fun in-jokes (nobody puts baby in the corner, but someone might put Harry Potter in a cupboard). And in the last half hour, the onion does begin to peel for John, who would otherwise come off as just the sort of tetchy, one-dimensional blowhard who may or may not have the actual talent to back up his swollen self-regard.

The ending lands with surprising emotional resonance too, though the impact of its final moments mostly serves to remind theatergoers that the rest of Lifespan could have used another, altruistic kind of fiction: more plot — and true emotional detail — than its bare facts can provide. B