Sam Shepard, at around thirty, is one of the three or four most gifted playwrights alive. His "The Tooth of Crime" is … strong and vivid and funny…. The play, like Mr. Shepard's wonderful "The Unseen Hand," of several years ago, is a comedy with science-fiction trimmings. It is about an aging and garrulous fellow of the Old West called Hoss, whose control of his territory is threatened by a "new" man, an icy, impersonal, taciturn young fellow called Crow. The play is also about the nature of fantasy (Mr. Shepard may be the first dramatist since [Luigi] Pirandello to bring us news on the subject of illusion and reality) and about power and feeling and the end of romance, and in the Old West Shepard has found the perfect setting for his ideas. "The Tooth of Crime" could be considered an allegory, I suppose, but let's not. It...