For its opening show of the season, the Shakespeare Theatre at the Folger, which is largely devoted to the plays of a genius, is doing a piece of hackwork for a change.

It is "The Witch of Edmonton," which the Jacobean playwrights Thomas Dekker, John Ford and William Rowley churned out in 1621 to capitalize on a sensational witchcraft trial of the day. Although it is billed as a tragicomedy, its tragic elements are the stuff of melodrama and its comedy is decidedly low. A melofarce, perhaps?

Still, lesser plays can serve a purpose. As much as the masterpieces, they give you a feel for the temper and popular taste of the past. Here are sentiments that once unleashed copious tears, shtick that tickled ribs, demons that inspired nightmares. If you can keep a historical perspective, "The Witch of Edmonton" is not bereft of interest. If you can't, it is likely to strike you as inflated and ludicrous.

The playwrights certainly can't be accused of stinting. The script finds a place for bigamy, seduction, transformations, madness, hysteria, murder and a morris dance. Much of the evil is perpetrated by the Black Dog, the Devil's crony, played by actor Wendell Pierce, who wears a wig of gnarled tresses and a leather jockstrap and scampers about on all fours. (When he rises on his hind feet, he looks rather like an exotic dancer from the Folies-Berge`re, but I am losing my historical perspective.)

Elizabeth Sawyer (Mary Lou Rosato), a poor woman of Edmonton, is so beset by the cruelty and meanness of the townsfolk that she enters into a pact with the Black Dog and so becomes the Witch of Edmonton. In my book, the townsfolk are asking for it. But the playwrights feel otherwise, and her eventual trial and hanging are meant to stand as a warning to those who would traffic with darkness.

No Jacobean play worth its blood ever settled for just one plot. This one also traces the destiny of Frank Thorney (Derek D. Smith, who was better off as last season's Romeo). A serving man, he has married the lowly Winnifride (Kim Staunton), a serving girl. Since he eventually hopes to escape poverty and share in his father's estate, Frank has kept the marriage secret. His father, however, is close to ruin and the family fortune can be shored up only if Frank marries Susan (Leslie Geraci), the daughter of a rich yeoman.

So he marries her, too. I realize this is sounding more and more like the 17th-century equivalent of "Days of Our Lives," but that's the point. If they'd had television back then, everyone would probably have come running in from the fields at noon to catch "The Witch of Edmonton."

What will the Black Dog be up to today? Will Frank tell Susan he's also wedded to Winnifride? Why is Frank taking Susan on a long trip and where did that nasty dagger come from? Is Elizabeth Sawyer really a witch or does she just have a lousy wardrobe and wear a lot of hay in her hair? If the suspense is too much to bear, there is always Cuddy Banks (Joel Miller), a plump countryman, to jump in a pond for comic relief.

Dekker, Ford and Rowley may not have reached the peaks, but they kept the pot boiling, prats falling and the Black Dog popping up in the darndest places. The trouble with the Folger production, staged by British director Barry Kyle, is that it is not content to leave things at that. Kyle apparently views "The Witch of Edmonton" as a neglected masterwork, shot through with penetrating psychological insights and great veins of compassion.

I'd like to believe him. But the evidence at the Folger speaks otherwise. The play's pedestrian language doesn't begin to support all the fervid emotions, and the actors, while giving the script their best efforts, look like so many canoeists up the stream without a paddle. Camp is a real and present danger here and the production, undertaken in collaboration with the Acting Company, doesn't steer clear of its pitfalls.

The tale unfolds in a weatherbeaten barn, designed by Joel Fontaine, and Kyle manages to exploit just about every nook and cranny. There is a goodly amount of physical action, which may be why Kyle ropes off a patch of the stage periodically to create a makeshift boxing ring. For all the last-minute repentance they display, the characters are a vicious lot, quick to brandish chains, farm tools and blazing torches. And Rosato, poor thing, is usually on the receiving end and in a dither. If nothing else, she deserves a nightly massage after the show.

Kyle has said that he sees "The Witch of Edmonton" as a precursor to Arthur Miller's "The Crucible." I suppose there are parallels. Both examine the sexual hysteria that usually goes hand in claw with witch hunts; both suggest that fanaticism is an outlet for the dispossessed and that it is often fanned by the haves in order to keep the have-nots in their place. But I dare say this is an academic pursuit, more appropriately conducted in an ivory tower.

Onstage, "The Witch of Edmonton" is a ragged, rugged sprawl, plainly calculated to stir strong emotions in the rabble. We have other ways of accomplishing the task these days -- among them horror films, demolition derbies, mud wrestling and Joan Collins mini-series. But if "The Witch of Edmonton" is pretty hard to buy, you can at least see how they might have bought it in 1621.

In more ways than one, a hairy black dog that suckles at its victim's teat is nothing to sniff at. The Witch of Edmonton, by Thomas Dekker, John Ford and William Rowley. Directed by Barry Kyle. Sets, Joel Fontaine; costumes, Judith Dolan; lighting, Nancy Schertler. With Derek D. Smith, Kim Staunton, Edward Gero, Edward Conery, Leslie Geraci, Mary Lou Rosato, Joel Miller, Wendell Pierce. At the Shakespeare Theatre at the Folger through Nov. 22.