“Pillowman” playwright Martin McDonagh appears at the 2008 Sundance Film Festival to promote “In Bruges.” (Photo: qbac07)

Martin McDonagh’s “The Pillowman” plays the Loeb Drama Center Experimental Theatre at Harvard University for the next week and is filling performances fast. The Friday show had a large waiting list; Saturday’s show was similarly sold out; there are a few seats available for Sunday and Wednesday.

Granted it is showing in the experimental theater, but the experimentation has gotten out of hand. This is a production that could benefit from a director having fewer ideas, and possibly fewer resources.

The play’s U.S. premiere was on Broadway in 2005 with Jeff Goldblum and Billy Crudup, and — clever and strong, with a cast of six or fewer and low design requirements — it has since become a popular choice for small companies, colleges and even, despite the brutality and cursing, high schools. The Harvard-Radcliffe Dramatic Club strips it down to four performers for eight roles, with the main ones being Katurian, a writer, and Tupolski and Ariel, police in an unnamed totalitarian state who have abducted him for questioning.

Also caught up in the investigation is Katurian’s older brother, Michal, who in the Harvard production has been turned into his twin sister.

That’s just the first of the conceits complicating McDonagh’s script. Changing the sex alone might have been okay, but director Ilinca Radulian seems to have added an incest subtext that I don’t remember from Broadway, when the brother was played by a beefy and, appropriately for the role, cloddish Michael Stuhlbarg.

There’s also been a large cube built that, when wheeled around, can be looked into to serve as jail cell or child’s room. Each see-through plastic wall of the cube has a door in the center that seems to snap shut with satisfying magnetic solidity. It’s all fancy but unnecessary. At one point, sheets of butcher paper are taped to the doors so movies can be projected onto them. It is hard to hear and see what is going on in the movies, which makes them also fancy and unnecessary. (And the cube, more than any other bit of stage direction in this production, forces the action so far forward that the actors can at times be only a couple of feet from one set of audience risers — making for awkward sight lines, especially when there are risers in three of four compass directions.)

The police have a stack of paper that represents all 400 or so stories Katurian has written, and each piece of paper has a large hole cut in its center. Whatever this means, it is distracting and unnecessary. The audience first thinks it is an error and tries to ignore it, then realizes it has been done on purpose and, while the drama onstage charges ahead, thinks: There are holes in all the papers. Why? The holes are in the shape of something. What is it? The holes make it hard for the actors to hold the paper. What do the holes mean? What does the shape of the holes mean? I can’t tell what the shape is. Am I supposed to? Is it the same shape in each? Am I supposed to be thinking about this?

Directors make choices, and Radulian, 25, a senior performing-arts major, has chosen also to seek some sophisticated choreography from Ricky Kuperman. Whether it’s the beating of the prisoner, the moving of a limp body or a dance that briefly and surprisingly defies gravity to put one partner standing on a wall, the choreography is well done. But is it necessary?

Radulian would have done better to focus on what the actors are doing when Kuperman isn’t in charge, including the problematic blocking and some aspects of the performances. Jackson Kernion, who plays the sly detective Tupolski, is a brave actor, but he talks low and fast, enunciating McDonagh’s crisp language poorly. Dan Giles as the more obviously violent Ariel goes right over the top in nearly everything he does — again, a brave performance, but this isn’t a silent movie. And after a while it seems like most of the emotions in the play are communicated by slamming or pounding things. This too ultimately distracts from a script by a master wordsmith writing about the power of writing who, it has been argued, purposefully injected into “The Pillowman” stage directions nearly impossible to act out but easily imagined by a reader or listener. And Katurian’s O. Henry-like short stories, which are actually McDonagh’s own youthful work repurposed, are all narrated.

If McDonagh weren’t such a master (he wrote, among many, “The Beauty Queen of Leenane,” the current “A Behanding in Spokane” and the screenplay for “In Bruges”), he might come in for blame for writing a dull play that needs jazzing up because it’s about a sedentary craft. But that’s not the case. “The Pillowman” is arresting, shocking and thought-provoking on its own, full of twists and anxiety. Questions about the moral responsibility of writers, and for that matter readers, authoritarians and censors, aren’t what’s distracting about this play.

Radulian may not have trusted that. She needs plays that better suit her restless creativity.

“The Pillowman” plays the Loeb Drama Center Experimental Theatre at Harvard University, 64 Brattle St., at 7:30 p.m. Sunday, Wednesday, Thursday, Friday and Saturday. Tickets are free and can be reserved through [email protected].[email protected].