They appeared on Broadway more than 20 years apart, but after you see Doubt and Agnes of God presented together as The Catholic Repertory by the American Theater Company (ATC), you might start to wonder if they weren't destined for each other in some strangely cosmic way.

Aside from the habits and other obvious Catholic trimmings, both plays involve three central characters brought into conflict over the most taboo and egregious of secrets imaginable, matters so disturbing and troubling that they shake each of them to both their moral and mortal cores.

In Doubt, a Catholic school principal suspects a priest of foul play with an altar boy. In Agnes of God, a psychiatrist searches for the truth from a young nun accused of giving birth and killing the child. Both plays are far from steeped in religious discourse; rather the Catholic context serves to amplify the severity of these crimes.

These are intimate stories with far-reaching consequences that extend beyond the walls of the Church, and the cast of Kate Skinner, Lance Baker, Penelope Walker and ATC ensemble member Sadieh Rifai capture this powerful range of big ideas and deeply personal issues under the direction of ATC Artistic Director PJ Paparelli.

There are moments in both plays when the unusually wide space at ATC feels intimate and times when it feels cavernous. It's as though Paparelli keeps gives the audience a microscope and then takes it away, over and over again. On occasion it's the nuance of the fine performances that steal our attention and at others the weight of ideas present in these fine plays.

The three leading ladies populate both works, with the most intriguing juxtapositions coming in the form of Skinner who plays Sister Aloysius in Doubt and Mother Miriam Ruth in Agnes of God and Rifai who plays Sister Agnes and Sister James. Aloysius and Miriam Ruth are cold and steadfast in their diametrically opposed beliefs, whereas Agnes and James represent two extremely different notions of naivety. The overlap thematically is simply uncanny.

Individually, each play could start the same discussion, fascinatingly enough, but it's the ways the two works speak to each other makes for the most stimulating conversation. Doubt remains the better of the two from a writing standpoint, but Agnes of God is far more dramatic and grabbing.

ATC makes both worthwhile. What seems as though it would be a dour double dose of a faith-based theater proves to be anything but constricted and preachy.