In the prop department at Center Stage, crew members have worked themselves to the bone for their latest production.

They had to create nearly 200 realistic-looking skulls and 400 femur, humerus and radius bones — not to mention pelvises — needed for the run of Martin McDonagh's bleak and brilliant comedy, "A Skull in Connemara," which closes next weekend.

At each performance, two actors go through a pulverization ritual in Act 2, seizing mallets and laying waste to three skulls and a handful of other human remains sitting on top of a big wooden table. It's one of the most startling scenes in contemporary theater, especially for anyone sitting close to the stage.

"Things come sailing out at you," said actor Jordan Brown, who does half of the pounding. "It's better than 3-D."

Brown plays Mairtin, a thick-as-bricks bloke in a forsaken Irish town where graveyard space is at a premium. After seven years, unsuspecting rest-in-peacers are dug up so that the freshly deceased can be buried.

The now decidedly decomposed former residents are then disposed of, their skeletal selves given a good pounding, the residue swept up for disposal.

"I'm always amazed at the response in the house when the first skull gets hit," said Si Osborne, who plays Mick Dowd, chief gravedigger, skull-basher and possible wife-killer. "You feel a big intake, almost a collective shriek."

It would be a huge letdown if, once Mick and Mairtin started wielding their mallets, the sight and sound did not match the audience's worst fears. Sure enough, each crack is enough to chill you to the bone.

That's because Nathan Scheifele, properties manager at Center Stage, made sure that there were finely made props to match the rest of the quality in this high-voltage production.

The process started with an online search for a good skull to use as a mold.

"We backfill the eyes and the nose with clay," Scheifele said. "Plaster of Paris is poured into the mold, which can be challenging. You've got a couple pounds of plaster in there sloshing around that you don't want leaking out of the skull."

The mold is covered with urethane rubber that is glued together — a step that, according to one of the crew, takes 11 minutes (and another six minutes to remove). More than one layer of plaster is poured for each mold, requiring sitting time in between.

Six hours after the process begins, a skull is born.

"We shellac them after they've been sitting a few days," Scheifele said. "That helps with the color, and it also soaks into the plaster so it will break into larger pieces when it's hit."

The bone molds are less complicated to deal with but follow a similarly time-consuming path to becoming stage-ready. In a typical eight-hour day, two shows' worth of skulls and bones can be created.

"There were some misfires early on," Scheifele said. "The first formulas left some huge air bubbles. And with some of the skulls, the jaw fell off and stayed in the mold. And the first skulls broke into tiny pieces when they were hit; they went from skull to dust in one hit."

Modifications were quickly made. It was discovered that watered-down glue would help hold the props together, avoiding that straight-to-dust scenario.

"And we want it to stay a little wet on the inside of the mold," Scheifele said, "so that [the skull when hit] doesn't sound like shattering glass."

By this point, after going through two dozen 25-pound bags of plaster of Paris, enough bone-creation has taken place to see out the last week of performances. The props neatly line shelves backstage, like a mini-catacomb.

After more than four weeks of bone-crushing performances, "the mallets have held up fine," Scheifele said. "The table, on the other hand — they've done a nasty job on that. I had to replace several boards and add steel braces. Last week, I reglued the bottom of the legs."