LIKE A momento mori bared amidst a medieval feast, the Harvard-Radcliffe Summer Theatre's production of Eugene O'Neill's Mourning Becomes Electra horrifies while it captivates, an anomaly in a world of frothy fun and glitter. And like that sobering skull, the play, staged as it is in late July, reminds us that--both literally and figuratively--glorious summer will quickly fade to autumn and winter. O'Neill lets us know that even while comedy and music, sunshine and song still cast their spell, death and decay lurk inevitably in the shadows. They need simply wait.

For his now-familiar plot, O'Neill takes the ancient Greek legend of Electra and sets it in the weeks following V-J Day. Ezra Mannon returns home from the war only to be killed by his wife Christine in collusion with her lover. Daughter Vinnie and son Orin work their revenge. Like the House of Atreus, three generations of Mannons are cursed. O'Neill's insistence on parallels is at times heavy handed, though. The main characters' names, for instance, mimic too closely their Greek counterparts. Ezra Mannon for Agammemnon, Christine for Clytemnestra, and Orin for Orestes are unnecessary hints to the audience. The plot and title would alone provide the key to this latter-day tragedy.

Needless to say, the Mannons are not your typical family. The incestuous love Orin (Alek Keshishian) feels for his mother and the similar feelings Vinnie (Amy Brenneman) has for her father incite the pair to murder. Passion, jealousy, revenge and guilt ooze from the play like poisons. In O'Neill's hands, the characters' idiosyncracies give us modern insight into the psychological motivations for the original Greek figures.

More than any classical tragedian. O'Neill is obsessed with death-and neurosis. Orin, and to a lesser degree Ezra, are shattered by the horrors of war. And for all of the main characters, death eventually becomes the only reality. The sick not only destroy each other, but leave the healthy (such as the neighboring Niles family) irreparably scarred. Such an absolute pessimism is distinctly modern, and purely O'Neill.

THREE HOURS IN LENGTH, director Magaril's production varies widely in quality. The cast seems to walk through certain scenes, such as the mini-climax which occurs when Christine (Debbie Wasser) kills Ezra (Benajah Cobb). The underplayed emotions defuse the scene's potential. At other points, though, the tension is very real. A card game between mother and daughter and the final conversation between brother and sister provide a genuine spark.

Magaril's inventive use of the Ex stage, moreover, helps keep the O'Neill play from dragging. Using only alternating areas of light and dark, Magaril creates up to three rooms on the wide floor, breaking up the expanse that could drown a drama such as Mourning Becomes Electra. The small spaces force the players closer, keeping the energy level of the play from dropping too low. Magaril also makes good use of the Ex's backstage, setting some action in the passage behind the normal playing area. The enclosed area, almost a proscenium stage within the larger floor, simply by its framing, infuses any scene within it with emotion. Yet, the most impressive sequence is the end, produced only on the stage, but done much less traditionally than the rest of the play. Lit with harsh, direct white light rather than colored floodlighting, the scene takes on an cerie dimension. Gone is the division into rooms as space loses its objective reality. The players occupy the entire floor. Droning synthesizer music in the background completes the setting for the final confrontations and decisions. O'Neill's themes, death and guilt, engulf the whole stage.

While the show is generally well-done, the uneven acting prevents the play from being all it could. Brenneman convincingly handles the most difficult role of Vinnie, alternating between the emotionally childish "daddy's little girl" and the cunning, evil woman who twists people to murder or suicide. But her snarling performance leaves the audience unable to pity her character. This bleak production denies Vinnie the final redemption earned by a tragic heroine. The other demanding role, Orin, occasionally eludes Keshishian, as he has trouble at first keeping the war-weary boy diffident and still remaining in character. Happily, the actor warms into his part. The rest of the cast perform competently, though more rehearsal time might have afforded them a greater degree of control and confidence. There are no weak players, but the real star is O'Neill's work.

Light summer theater it isn't Brooding and ponderous, but never slow, Mourning Becomes Electra is as black and cold as funeral garb. A play of despair, it ends without hope. But for those willing to take the long day's journey into night, an imaginative, well-directed drama awaits.