Local audiences will be fortunate to be offered two plays by John Patrick Shanley this winter: Outside Mullingar, a delectable Irish romance now in previews at Philadelphia Theatre Company, and Doubt: A Parable, a profound and troubling drama opening in January at Lantern Theatre.

Together they represent the best, and the polar extremes, of a long and varied body of work, starting back in the day - 1987 - when we all fell in love with Shanley's Oscar-winning screenplay for the movie Moonstruck.

Doubt, which won the Pulitzer Prize and the best-play Tony Award in 2005, is a troubling, fascinating work about moral ambiguity. A popular and charming priest is suspected of sexually abusing a student at a Catholic school in the Bronx presided over by ironfisted Sister Aloysius. The engine of the drama is the truth that evades both characters and audience.

Outside Mullingar, which ran on Broadway in the spring, is a poignant romantic drama about Rosemary and Anthony, two fortysomethings living with feuding parents on adjacent farms in rural Ireland. She pines for a man who pines for her. The engine here is the need for love and inheritance.

In a recent phone interview from his New York home, when this lack of predictability in his work was noted, Shanley replied, "That's what I'm aiming for. I've just written a new play - which I'm not going to talk about - and I did another new play called The Danish Widow this summer up at New York Stage and Film [at Vassar College] with Kyra Sedgwick, and that was great fun to do, and then I came back to town and agreed to write and direct Outside Mullingar as a film."

However unpredictable his plays are, they are always, in some ways, about family and legacy, so it is especially interesting to hear Shanley, 64, talk about his parents. Chatting with him is easy, with his Bronx accent and immediate warmth. He replies to questions with anecdotes and aphorisms. Here are excerpts from our conversation:

Shanley: My mother and father were like salad dressing - my mother was vinegar, and my father was the rich olive oil. They needed each other, and I needed both of them - it gave me balance. I had a natural sense of optimism and buoyancy from my father, but I constantly came up against the ice-cold skepticism of my mother. It kept me realistic, when my natural tendency was to float away like a multicolored balloon.

Question: Your gusto for life has been conspicuous on Twitter lately ("I woke today unable to deny the overwhelming magnificence all around me. God, it's beautiful to be alive"). It's also obvious as far back as your famous dedication of the 1984 play "Danny and the Deep Blue Sea": "This play is dedicated to everyone in the Bronx who punched me or kissed me and to everyone whom I punched or kissed." I get the feeling that's a lot of people.

I fought the feeling of optimism and life-embracingness for a long time, and then I thought, why am I fighting this? I've had my share of tribulation in my life. I have advanced glaucoma in both eyes and I've had many eye surgeries, but I can read and drive a car, but the biggest thing is that I didn't think I'd live this long! The only sport I was ever good at was long-distance running, and that's a metaphor for what I try to do as a playwright.

What caused this shift from urban to rural, from the U.S. to Ireland?

My father was an Irish immigrant, came to this country from a small farm in central Ireland. His entire point of view was forged there, and I experienced it here. My uncles moved to New York, too - I had a lot of Irish going on throughout my childhood. My father played the accordion, and my aunts and uncles danced in the living room - a version of step-dancing - so when I went to Ireland for the first time, which was to take my father home when he got too old to go independently, as soon as I sat down in that kitchen, I realized, this is home. It feels more like home than my home did. So I always knew I'd write about it, but it took 20 years before I could. I never enjoyed writing anything as much.

Your plays, whether they take place in the Bronx or in Ireland, are always marked by the rhythm and accents of the spoken language.

Over the course of a lifetime you hear many distinctive patterns of speech and if you have a good ear, as I do, sometimes you go, "that's terrific" - but that was basically true of every Irish person I met. My uncle Tony and my aunt Mary lived on that farm [in Outside Mullingar], my cousin Anthony runs the farm and has never married but I still have hopes for him! And those gates [a key element in the play] have been on that land for 60 years.

It's always surprising when something that seems so literary turns out to be just reality.

I know when I wrote Doubt, somebody had an objection when the priest describes the "black boy," arguing that at the time he would have said "Negro," but I replied, "That's what he said. I was there." It's an irrefutable argument - if you know that as a playwright you can do it: I have the confidence of reality behind me.

Are you coming to Philly for the shows?

The first time I went to Philadelphia I had a feeling of recognition because it's a real neighborhood city and I come from a neighborhood place, you know, the Bronx, and that kind of urban vitality, mixed with a long history of immigration, leads to the sense of humor and gusto for life that I think would meld very well with this particular play.

So?

I travel very little, except if somebody says do you want to go to Paris, I say yes. But it's surprising how rarely anybody says that.

THEATER

Outside Mullingar

Through Dec. 28 at Philadelphia Theatre Company's Suzanne Roberts Theatre, 480 S. Broad St.

Tickets: $46-$59

Information: 215-985-0420 or philadelphiatheatrecompany.orgEndText

Toby Zinman reviews theater for The Inquirer.