Though "The Blood Knot" was staged just last month by the Washington Stage Guild, it's well worth it to take another look at Athol Fugard's 1963 drama. The American Showcase Theatre Company opens its new Alexandria theater with a superior production of the play, which compellingly condenses the tensions of apartheid into the antagonistic relationship between two South African half-brothers.

In a grim hovel on the outskirts of industrial Port Elizabeth live the Pietersons: Zachariah, who is undeniably black, and Morris, who, as Zach would say, is "on the lighter side of life." These half-brothers have an unsettlingly strange power over each other, one that Fugard never explains. For some reason, high-spirited Zach bows to his brother's will and remains in the house night after night. And Morrie, who had successfully passed himself off as a white man in Johannesburg, is drawn back home, guilt-ridden, to care for Zach and plan for their future together.

When Zach complains of loneliness under Morrie's rigidly regimented care, Morrie suggests he find a pen pal, and ghost-writes a letter for him. But when the correspondent turns out to be a white girl and announces her intent to visit, both men panic, initiating several bouts of frighteningly extreme racial role-playing that unearth painful family memories and reveal the nature of "color" and the illusory power it can provide -- or withhold.

In an energetic, finely tuned performance, Bill Grimmette reveals a complexity beneath Zach's surface simplicity. As the more enigmatic Morrie, Nat Benchley comes up with a convincing South African accent and effects an unnerving transformation in the role-playing scene. Working within a traditional staging format (the Washington Stage Guild's in-the-round production was ill-suited to this play), director Jill Kamp negotiates a balance between violence and humor and sets a lively, compressed pace that somewhat compensates for the play's tendency to ramble. Kamp has also underlined the memory sequences of the drama with melancholy fragments of South African music.

The new 60-seat theater is a comfortable one, located in the Station Shops plaza, a block from the King Street Metro stop. The Blood Knot, by Athol Fugard. Directed by Jill Kamp; setting and lighting, David McCandlish; costumes, Rosemary Pardee-Holz. With Nat Benchley and Bill Grimmette. At American Showcase Theatre through Nov. 22.