Despite vigorous admiration from influential critics (the New Yorker's Brendan Gill found its ""nimble, crisscrossing cat's cradle of a plot"" . . . ""exceptionally provocative"") and despite the onstage presence of luminous Maria Schell, Poor Murderer failed to hold on to the Broadway patrons for more than a few months. It's their loss--for Czech poet-screenwriter Kohout's export is a fascinating amalgam of mystery story, clinical case study, and social commentary--all of it draped in desperate repartee and sheer theatricality. On a makeshift stage--for an audience of one--insane(?) great-actor Kerzhentsev stages his life of definite obsessions and possible crimes, instructing the bewildered actors to follow his painfully personal, Hamlet-entwined script. Unfortunately, the printed text doesn't distinguish typographically between the lines of the play and those of the play-within-the-play, making this a rather trying reading experience. But enough of the dramatic force charges through to make one wonder if perhaps Kerzhentsev (played in New York by solid but unmagnetic co-translator Luckinbill) doesn't demand-like the comparable madmen in Pirandello's Henry IV and Bellow's Last Analysis--a performance of monumental stature. Blessed with such a rendition or not, Poor Murderer will no doubt reappear--in New York and elsewhere--and will be welcome when it does.