Most aficionados agree that the point of modern art, assuming there is one (and there are plenty who insist that pointlessness is the point of modern art), is to challenge and destroy the deceitful illusion of surfaces. Traditional art is all about surfaces: a picture of a man skiing down a hill is just a picture of a man skiing down a hill. But in most modern art, especially abstract art, the true meaning of a painting works deep beneath the surface. In fact, the less a painting appears to resemble anything recognizable, the more powerfully it is able to work on a viewer's emotions, expectations and intellect.

Or something.

This view of art, of course, is sheer, incomprehensible nonsense to people like the opinionated Marc, one of three deeply layered characters in Yasmina Reza's sharp-witted, Tony-winning comedy Art, running through Jan. 23 in the Studio at the Sixth Street Playhouse. Marc (played with ferocious derision and thinly veiled hurt by the excellent Tim Kniffin) is still reeling from the news that his longtime friend Serge (Dodds Delzell, focused and funny) has spent a small fortune on a painting of . . . nothing. The large, unframed canvas is totally white, with almost imperceptible white diagonal lines.

Serge, a Parisian dermatologist, can certainly afford the 200,000 francs he coughed up for the painting, and he genuinely likes it. But Marc's negative reaction ("It's a white piece of shit," he says) puts an immediate and increasingly powerful strain on their friendship.

Caught in the middle is Yvan (an elastic Tim Setzer, channeling a young Nathan Lane, with a dash of Stuart Smalley). Yvan, facing an impending marriage to a woman he's not sure he's right for, is alarmed to see his primary safety net (his position as the affable third party in the Marc-Serge-Yvan trio) beginning to come apart, and his ineffectual attempts to calm things down only make matters worse.

There is plenty of witty discussion on the meaning of art, much of which plays right to the edge of satire. Terms like "deconstruction," "inertia," "masterpiece" and "monochromatic resonance" are tossed around like cashews spilled from a bowl. But despite all of this, Reza's brilliant Art is not really about art; it's about friendship and the illusions that hold people together—and, in some cases, tear them apart.

Elegantly emphasized by director Jennifer King, the forces that have worked so well in the trio's 15-year friendship reveal themselves to be less about mutual tastes and interests and more about pecking order. What hurts Marc so much about Serge's impulse buy isn't the painting so much as Serge's uncharacteristic self-determination. There was a time when he'd never have made so bold a decision without consulting Serge first, and that, more than anything, is what plunges Serge into his state of unease.

The play's resolution is at once shocking and emotionally satisfying, as the three men, their friendship's true meaning suddenly brought into the cold light of critical analysis (or should I say "deconstruction"?), inevitably find a way to their own natural shape and form. The crafty, fine-tuned cast finds clever ways to launch this already amusing material into escalating levels of comedy, while staying grounded in the recognizably sad and silly fallibility of simply being human.

Human frailty of another kind is explored, with far less elegance and insight, in Noah Haidle's aggressively unpleasant, intermittently funny dark comedy Mr. Marmalade. Presented at Spreckels Performing Arts Center by the Narrow Way Stage Company, Haidle's play is like a Saturday Night Live sketch (one of the early, take-no-prisoners kind), stretched out to 90 minutes and pushed to the very edge of acceptability. OK—it actually goes way beyond acceptability, and that quality of the play's sheer boldness and gutsy in-your-faceness is its most appealing feature. Unfortunately, that's not enough to make this comic exploration of psychological damage and child neglect any less squirm-inducing.

Lucy (Caitlin Brandon) is a four-year-old New Jersey girl whose mother either leaves her alone or in the company of criminally careless babysitters for hours at a time. Left to a television diet of Disney princess movies (and daytime talk shows), Lucy has developed a seriously unhinged coping method: she's created an imaginary friend who springs from the most dire and unfathomable details of the screwed-up adults she watches on TV.

Mr. Marmalade (played with creepy child-molester intensity by Matt Witthaus) is an overworked businessman with porn movies in his briefcase and a penchant for snorting coke who can only play with Lucy for short periods of time, scheduling make-believe tea parties between days-long business trips. More often, Mr. Marmalade sends his gay, physically abused personal assistant Bradley (Clint Campbell) to take his place.

All of this is intentionally distasteful, and yet not without moments of icky but laugh-inducing farce. When Lucy temporarily breaks up with Mr. Marmalade, she dallies with a real-life playmate, the whimsically depressed Larry (Patrick Reilly), who at five years old has been named the youngest attempted suicide in New Jersey history.

Reilly plays Larry with an appealing sweetness, and for a while, their games of playing doctor (including pantomimed heart transplants) are kind of endearing. With the arrival of Larry's own imaginary playmates—freakish humanoid vegetable people with childishly flatulent senses of humor—Lucy makes up with Mr. Marmalade and descends into a child's version of an unhealthy abusive marriage, ultimately leading to some rather graphic staging of infant murder (don't try this at home, kids) and seppuku (which, OK, was kind of funny).

All the while, director Lito Briano keeps the tone cartoonish and slapsticky, undermining whatever vague social commentary the playwright may have intended. Narrow Way has made a name for itself by tackling tough, polarizing material, and this play certainly fits that MO, but with nothing coherent to communicate beyond a spirited willingness to offend, Mr. Marmalade is merely an exercise in prankish discomfort.

'Art' runs Thursday–Sunday through Jan. 23 in the Studio at the Sixth Street Playhouse. Friday–Saturday and Jan. 20 at 8pm; 2pm matinees Sunday and Jan. 22. 52 W. Sixth St., Santa Rosa. $10–$25. 707.523.4185. 'Mr. Marmalade' runs Thursday–Sunday through Jan. 23 at Spreckels Performing Arts Center. Thursday–Saturday at 8pm; Sunday at 5pm. 5409 Snyder Lane, Rohnert Park. $10–$15. 707.588.3400.

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