THE FAITH HEALER. a play by Brian Friel. Directed by Jose Quintero; scenery by John Lee Beatty; lighting by Marilyn Reneagel; produced by Morton Gottlieb with Ben Rosenberg and Warren Crane.

With James Mason, Clarissa Kaye and Donal Donnelly.

At the Morris A. Mechanic Theatre. Hopkins Plaza, Baltimre, through Mar. 31.

Is there anyone capable of filling a blank piece of paper faster than an Irish playwright?

The ordinary author, lacking extraordinary inspiration, stares desperately at all that vacant whiteness and weighs suicide. But the Irish playwright gazes calmly at the same bare page, begins to ponder the grain or the watermark, composes a sprightly, lyrical sentence or two, and suddenly has his first act in hand.

Unhappily, after a few hits he may grow weary of such conventional dramatic bric-a-brac as beginnings, middles and ends, and yearns for something more exotic.

It was in such a mood, I suspect, that Brian Friel, author of "Philadelphia Here I Come," came to write the provicative but exasperating work that opened Tuesday night at Baltimore's Mechanic Theatre.

With the aid of James Mason -- making his first stage appearance in 32 years, and choosing an uncomfortable part for the occasion -- Friel has set out to capture an audience through the nonstop flow of language and ideas. Each of "The Faith Healer's" four acts -- are you ready for this? -- is a monologue. No two actors occupy the stage simultaneously.

The play is a about faith healing, and in broader terms -- Friel uses much broader terms -- about talent, artistry and genius, their nature and proper care and feeding.

Nine times out of ten Fantastic Francis Hardy, Faith Healer ("One Night only"), leaves his desperate, deformed patrons exactly as he finds them. Just what happens that miraculous tenth time, even Hardy admits he has no notion. He has a "unique and awesome gift" sometimes, and sometimes he hasn't.

His manager Teddy, although equally baffled by the source of Frank's power, has a lot to say, rhapsodically and acidly, about those so possessed (and Donal Donnelly, an Irish actor of chameleon-like range and proportions, makes Teddy and his speech the play's unassailable high points).

Teddy has worked with quite a few artistic geniuses in his day, and he has noticed a few traits they seem to have in common.

Rob Roy, the Piping Dog, for example, was a whippet who could play "Come Into the Garden, Maud" on the bagpipes. "Marning, noon and night he'd sit there blowing the bloody thing and working them bellows with his back leg," says Teddy. "... And brains? Let me tell you.I had that dog four and a half years, until he expired from pulmonary exhaustion. And in all that time that whippet couldn't even learn his name!"

Rob Roy, Fantastic Frank, Houdini, Laurence Olivier -- all great artists, says Teddy, and "not one of them has two brains to rub together."

"The Faith Healer" has several enthralling passages of this sort, but it is not cumulatively enthralling. The audience chatter at intermission and after the final curtain was thick with synonyms for "confused" and "exhausted," and no wonder.

Beyond its rich language and highly stimulating subject matter, "The Faith Healer" crawls with shrewdly calculated discrepancies, ambiguities and tiny mysteries that unfold, Rashomon-style, in the successive testimony of its three characters. But Friel has made puzzling it all out, or even identifying all the puzzles, too much work and too little play.

James Mason's Australian wife, Clarissa Kaye, is also his wife in "The Faith Healer," a result of their deliberate search for a play they could play in together. Kaye is disoriented, frazzled and right as this ignored wife, but Mason, as the faith healer, has made a poor choice from his point of view and the play's. The part demands a larger-than-life performance, and Mason's brilliance -- splendidly displayed in "Odd Man Out," "A Star Is Born," "Lolita" and a string of other good and bad films -- lies in tight, closed, even contorted, parts.

He should take better care of his gift.