Chicago in the 1870s was ground zero for talking with the dead. By one estimate, Chicago spiritualists—believers and practitioners—numbered roughly 10,000. Extraordinary, given that the city’s first medium didn’t show up until 1849, and her first convert was committed to an insane asylum four years later.

Spiritualism began in America in 1848, when two sisters allegedly heard the knockings of an alleged peddler who’d allegedly been murdered in their Hydesville, New York, farmhouse. Their father invited the neighbors to hear, and soon the sisters were touring the country, making spirits appear in lecture halls and private homes. In short order, other mediums—as many as 30,000 of them, mostly women—were making tables levitate and spectral hands appear in darkened parlors across the country.

Chicago’s spiritualist community was put on the map in 1856, when renowned psychic healer Andrew Jackson Davis (he claimed he could see into the body and identify diseased internal organs by their diminished luminosity) paid a visit to anoint his local followers. Less than a decade later the first national convention of spiritualists met in Chicago, and the weekly Religio-Philosophical Journal was rolling off a Chicago press. Then, in 1875, America’s most famous medium, Cora L.V. Richmond, settled in Chicago. She led a huge congregation here and achieved such renown that in 1912, more than a decade after the spiritualist craze had faded, the New York Times printed all ten paragraphs of the message she said she’d received from a victim of the Titanic disaster.

The typical medium may have been a skilled con artist (one mail-order catalog provided everything necessary to fake a seance), but the political ramifications of spiritualism were real and profound. Mediumship gave Victorian women a singular opportunity to defy restrictive social norms and achieve financial independence. And the spiritualist belief in the intermingling of humans and ghosts bolstered support for other unconventional interminglings, most notably free love. Medium and free-love advocate Victoria Woodhull even ran for president in 1872.

A playwright could hardly ask for a more evocative milieu than the world of 1870s Chicago spiritualism, and that’s precisely where Emily Schwartz sets her Strange Tree Group premiere The Spirit Play. She and the company reportedly spent a year researching original source material for the piece. Yet the finished product is an expedient, creaky, inconsequential riff on exhausted Victorian cliches. Worse, it’s credible only if you assume that all the characters are morons.

The Spirit Play is set in the well-appointed parlor of starchy Mrs. Redspell, who displays no more character than her furniture. She convenes the Buchards—a bereaved mother and her skeptical physician husband—along with a drunken, recently widowed neighbor, Mr. Tennant, for a seance in her home. Also present but lacking any stake in the action are Mrs. Redspell’s preternaturally swishy son, Hubert, and his two sexually repressed female friends. The medium, Jane Foust, and her abusive, cutthroat husband, Gerard, conduct seances as a screen for committing petty theft (rather than just, say, charging a fee).

During the protracted seance, characters grope about as if they can’t see anything even within a few inches of their faces. I guess they’re supposed to be in total darkness, though the stage lights are gradually coming up throughout. Gerard tiptoes around—blowing on people, brushing them with feathers, sliding under the table to produce ghostly knockings. He’s an idiot for thinking such broad movements in close quarters would fool anyone. But then the guests, demonstrably not blind or deaf, are idiots for being fooled. Oddly, they’re all able to see a rose from across the room.

And so it goes. Schwartz and director Jimmy McDermott rarely do the hard work of making con artistry, supernatural occurrences, plot turns, or human behavior convincing. Twice Dr. Buchard scours Foust’s medium cabinet for signs of trickery, and twice he overlooks a trapdoor that’s visible from the second-to-last row in the audience. Mr. Tennant not only mistakes the medium’s secret accomplice for his dead wife’s ghost when he kisses her at midnight in a cemetery (OK, he’s drunk) but then believes she’s vanished when she takes two steps back and puts on a black cloak.

It doesn’t help that McDermott’s staging shifts arbitrarily from melodrama to farce to realism and back again. Schwartz’s ultimate interest seems to be the extremes to which bereaved people will go to believe in life beyond the grave. But unlike Victorian mediums, she gives us little reason to believe anything she shows us.