Face of a Hero opens with a vastly unsuccessful Prologue, done in mumbles and fake Southern accents. The play itself, based on what was obviously a magnificent conception by Pierre Boulle, at times repeats the hokiness and incomprehensibility of its opening scene. More often, however, it is entrancing, disturbing theater, and it leaves the members of the audience talking to themselves when it is over.

Robert L. Joseph adapted Boulle's noved for stage presentation, and he has not done an altogether satisfactory job. Too many of the characters are shockingly inconsistent, changing horses in midstream without even getting their feet wet. A number of extraneous considerations, notably the Negro problem in the South, are mercilessly appropriated to fill gaps in continuity.

The story, briefly, tells of David Poole, an ambitious county prosecutor (played by Jack Lemmon), who is able to forget that he is witness to a suicide in order to convict an innocent suspect and become a Hero. Albert Dekker as the sheriff eggs him on toward his hollow stand for Right and Justice, and James Donald as the deputy prosecutor warns him of the power the accused's family wields, which just set him more firmly in his course. But only a Negro secretary, Elizabeth Falk (portrayed by Ellen Holly) knows his secret.

This is a brilliant theme, and it leaves you with the same empty and puzzled feeling that Boulle's The Bridge on the River Kwai produced. But there are many things wrong with this play. The deputy seemingly turns from a fearless cynic to a jellyfish with startling rapidity, but his about-face is nothing compared to the prosecutor's. At the end of Act II, Poole is battling with a troubled conscience and trying to lead investigators away from evidence that tends to indict young Harold Rutland (played by George Grizzard). Soon after the beginning of Act III, however, Poole tears into a coroner who is evidently hiding such findings, and thereafter poses as a modern day Valiant-for-Truth.

Much is made of Elizabeth Falk's Negro blood, and eventually it is an appeal to her concern for her people that induces her not to spill the beans about Poole. Yet the Negro issue is a straw man forcibly dragged into the plot; it does not belong. Another gratuitous element apparently was invented to give Betsy Blair something to do. In her role as Mrs. Poole, Betsy minces on stage, makes several totally inane and unconnected remarks to two office secretaries and the baffled Poole, and then exits--for good. As one mystified man behind me said after her brief flurry, "What the hell?"

The script's attempts at shocking dialogue either fall flat or are pointlessly vulgar. There is, it should be noted, a difference between a shocking line and a vulgar one. In an effectively staged but poorly written suicide scene, young Rutland's speech alternates between teen-age hipness and Southern degeneracy. Rutland eyes Sandy Dennis (playing Millicent Bishop, soon to be a corpse) lecherously and leers, "We gone take it from the top." When Millie blurts out the news that she is pregnant, Rutland reacts all over the place: he babbles to himself, "Millie, Millicent, Millicentus..." He declares, "There is no faith except deep knee bends." He runs off the stage, screaming "Alarm! Alarm!" He sneers, "Your inside wouldn't hold anything of mine." He taunts, "I'll lend you a sweat shirt." Finally, having come at the problem from every conceivable angle, and with pointless filth three feet deep on the stage, he snarls, "I hate you."

Acting performances are, with one glaring exception, adequate or better. Miss Holly, in a pivotal part as Poole's Negro secretary, is often ludicrous in her intensity. But Lemmon is a success in his first big serious role; if he learns to vary his expression and tone of voice, he will be superb. As the sheriff, Dekker is magnificent, the dominant figure every time he is on stage.

Ben Edwards does a fine job on scenery and lighting, and Alexander Mackendrick's directing seems adequate, although he must do something with the unfortunate Miss Holly and iron out the Prologue. But playwright Joseph has a lot of work to do.