One of the things that make opera all the more exciting comes when you arrive expecting a routine evening, and instead something happens that simply takes your breath away. That happened last night at Wolf Trap with the debut here of tenor Richard Leech as Pinkerton in the New York City Opera's "Madama Butterfly."

He has only been with the City Opera for a year, and general director Beverly Sills said last night that the company came upon Leech, of Binghamton, N.Y., in an audition. "He's somewhere in his twenties, and he came in and here was this voice," Sills said excitedly.

At this point in Leech's career it would be hard to conceive of a better tenor for the role of Benjamin Franklin Pinkerton, who in his relationship with poor Butterfly was the original "Ugly American." It lies exactly right for his voice; the evenness from top to bottom was flawless. Leech is so comfortable with the notes that he was utterly free to phrase and color Puccini's notes with imagination and lyricism. The highs were pretty dazzling, like those on the word "America." And his resonance was just gorgeous.

For Leech, the love duet in the first act could hardly have gone more gloriously. Catherine Lamy's Butterfly was splendid, but paired with Leech's kind of singing, the emphasis was off of her.

It's hard to know where this tenor voice will go. Sills has cast him as Rodolfo in "La Bohe me," which she said was truly fine, as well as Alfredo in "Traviata" and the Duke in "Rigoletto." She points out, though, that there is a baritonal timbre to Leech's tenor that might match him to the spinto roles. That is unquestionably there, but he ought to start out cautiously in such an area. The voice is just too beautiful to tinker with. He is also handsome and a fine actor.

The City Opera's "Butterfly" is a fairly simple and direct one, under Frank Corsaro -- at least by comparison with the Met production. This not necessarily a bad thing, because David Belasco's creation is so melodramatic -- and Puccini's music so powerful -- that it really carries itself when performed this well.

There are little details, like when Butterfly's servant Suzuki (sung warmly by Jane Shaulis) embraces the little boy sired by Pinkerton, that really touch the heartstrings.

Other especially fine performances: Douglas Perry as Goro, and Adib Fazah as Sharpless.

Christopher Keene conducted idiomatically and warmly. The Humming Chorus was particularly lovely.

This "Butterfly" will be repeated at Wolf Trap. It is a good one, and Leech is really worth going out of one's way to hear. It would be sad if he doesn't develop into a true star.