`CATECHISM' IS STAND-UP FOR SOUL.

Byline: Reed Johnson Daily News Theater Critic

She prowls the aisles like a Marine boot camp instructor, sniffing out sinners and gently chiding their errant souls.

``Could you have worn a shorter skirt, there, with your legs sticking out?'' she admonishes a young woman in one of the front rows at the Henry Fonda Theatre.

The faint Irish lilt in her voice intensifies as the irrepressible nun, known simply as Sister, hastens to dispense two Kleenexes so that the miscreant can cover her offending knees.

A minute or two later, Sister issues a $1 fine to a pair of latecomers, cheerfully observing that if her parish can raise another $4, it can adopt a ``pagan baby.'' At this beatific thought, Sister's blazing blue eyes, which you suspect could bore holes through a battleship, go soft, and her linebacker's shoulders slacken in blissful repose.

Don't be fooled, though, by this temporary lull in ``Late Nite Catechism,'' the boisterous, one-woman interactive passion play starring Maripat Donovan. Before you know it, this tireless soldier for Christ may be calling on you to recite the definition of ``Easter Duty'' or explain the Immaculate Conception.

Or perhaps she'll expound on the way Vatican II can embrace Darwinian theory while still maintaining that God created the world in six days. ``Those could've been really long days, like dog years,'' Sister speculates in a voice that bends waggish skepticism into deadpan certainty.

As portrayed, lovingly and hilariously, by the energetic Donovan, Sister could pass for one of those wise, stern, feisty, self-abnegating women who taught some of us how to read, write, do unto others as we would have done unto us, and never, ever use our ``playground voice'' indoors.

Donovan co-wrote ``Late Nite Catechism'' with Vicki Quade, and in so doing has spawned a cult hit and given herself a character she was clearly born to play, with a stockpile of snappy one-liners, droll double takes and not an ounce of mean-spiritedness. ``Late Night Catechism'' affirms the virtue of faith while conceding that faith sometimes can be a rigorous taskmaster.

Though slightly overlong at two hours, the show has a simple, sure-fire premise: Sister is conducting a night catechism class for adults, turning the audience into her students and allowing Donovan to rise to the energy level of those around her. Donovan's improvisational stamina, spot-on comic timing and flair for the give and take of audience participation testify to the many years she has spent pumping iron in Chicago's brawling theater scene.

Donovan needs all those tools and more because, of course, funny nuns and lapsed-Catholic humor aren't exactly novelties. But if the family-friendly ``Late Nite Catechism'' inevitably prompts comparisons with ``Nunsense'' and ``Sister Mary Ignatius Explains It All for You,'' it manages to be less calculatedly middle-of-the-road than the former and scarcely less sharp-witted than Christopher Durang's savagely funny 1979 play.

Neither a caricature nor merely a stand-up in sensible shoes, Donovan's Sister is one tough, soulful cookie - black and white and ready for whatever. Let us all pray for an extension.

THE FACTS

What: ``Late Nite Catechism.''

Where: Henry Fonda Theatre, 6126 Hollywood Blvd.

When: Performances at 8 p.m. Tuesdays through Fridays, 2 and 8 p.m. Saturdays, 3 and 7 p.m. Sundays; through June 6.

Tickets: $32 to $37. Call [phone].

Our rating: Three and one half stars.

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Photo

Photo: Religion takes a back seat to humor in ``Late Night Catechism,'' starring Maripat Donovan stars as the irrepressible Sister.