MOST PEOPLE ONLY know Wallace Shawn as an actor, the delightful gnome who first bubbled into consciousness as the "homunculus" in Manhattan. But Shawn is also a dedicated playwright, creating works so challenging they have gone largely unappreciated. Even Shawn and André Gregory's provocative My Dinner with Andrébears little resemblance to Shawn's uncompromising plays. In them the primary relationship is not between characters but between the play and the audience, with the play operating less as a sparkling symposium than as a loaded gun.

It's astonishing, then, that Berkeley's Last Planet Theatre should be mounting a four-play, monthlong Wallace Shawn Theatre Festival. Two plays a night are presented in rep, all staged by artistic director John Wilkins and produced by Kimball Wilkins. Last Planet began its life in January, and only a company this young would have the chutzpah to undertake such a noble, demented enterprise. Marie and Bruce,Shawn's most-produced play, is also one of his best. At the start of this day in the life of a New York couple, Marie plans to leave her husband, whom she showers with a barrage of vicious epithets. The couple agree to meet later at a friend's cocktail party, a nightmarish function that not only reveals Bruce's selfish, icy heart but also that of the society in which the couple moves. Their static purgatory, just this side of hopelessness, is Shawn country, which for all its cruelty and uncertainty has flashes of absurd, redemptive wit.

Marie and Bruce is paired with Our Late Night,seen here in only the second production since its 1975 premiere. The two plays are surprisingly similar, both focusing on sophisticated parties that take surreal turns. Here the revelers forgo polite chitchat for open admissions of their desires, which are crudely sexual and violent. But there's a clear moral purpose underneath all this brutality: a palpable nausea (vomiting and weeping are Shawn's most common stage directions) runs throughout these plays, a shame and sickness at how twisted modern life has become.

Shawn's social critique becomes more pointed in the festival's second evening. The protagonist of Aunt Dan and Lemonis an anorexic Englishwoman called Lemon who spends her childhood under the influence of a family friend. Aunt Dan's bracing iconoclasm discloses a soul bereft of compassion, one that rationalizes and even enjoys murder. Her tutelage deforms Lemon into a woman capable of admiring the Nazis for their lack of hypocrisy. No one in the play ever counters Dan's and Lemon's glib, monstrous arguments, and Shawn leaves us to concoct our own rebuttals. The final play, The Fever,is a solo that details its privileged narrator's mounting awareness of worldwide suffering and his consequent guilt. It represents Shawn's most direct statement about the need for human connection, for radical changes in things as they are.

Despite his clear-sighted gifts, Shawn can be a maddening dramatist. These plays often consist of monologues disguised as dialogue, locomotives of language whose delivery constitutes the only action. Although John Wilkins clearly understands the plays, his staging is loaded with freshman-director excesses: wildly overchoreographed moments, too many sound cues, and some downright loopy, unjustified concepts—such as a Noh-masked chorus in Marie and Bruce.But when he sticks to the script, Wilkins creates some sublime moments. The solo limits of The Feverhave a salutary effect; Wilkins devises subtle physical rhythms and lets the words do the work. The rest is up to actor Richard Reinholdt, without whom this festival would be unthinkable. Reinholdt is superb in all four plays, but his sensitive performance in The Feveris an absolute knockout. He's also terrific as the emotionally stunted Bruce, matched by Tiffany Hoover in her exquisite work as Marie. Tori Hinkle's Lemon is the other standout, a bone-chilling portrait of a warped, heartless child. I'd pick The Feveras Shawn's best work here by far—fierce, immediate, and touching. My vote for second best would be Marie and Bruce,an underrated play that here finds its Joycean soul in rich performances. Despite the uneven nature of these productions, I give Last Planet a standing ovation for making the attempt. The company's energy and enthusiasm throughout these marathon evenings is tireless, frequently covering shortfalls in professionalism and polish. Its single-minded dedication to helping these difficult, important plays become better known reflects the best kind of theatrical impulse. That Last Planet succeeds as much as it does promises wonderful things for the company's future.