It's a night of firsts this evening at the Metropolitan Opera, as the company opens a new production of Gluck's final masterpiece, Iphigenie en Tauride.

The staging, by director Stephen Wadsworth — soon to become the Juilliard School's first Director of Opera Studies — is the Met's first co-production with Seattle Opera. On the podium is Louis Langree, music director of Lincoln Center's Mostly Mozart Festival, giving his first performances at the Met. Supertenor Plбcido Domingo sings for the first time the role of Oreste, the 124th part in his repertoire. And this will be New York's first opportunity to hear Susan Graham as Iphigйnie, a role she has sung to resounding acclaim in London, Chicago, San Francisco, Paris and Salzburg.

Not least, this production marks the first time the Met has presented Iphigenie en Tauride since 1917.

Tenor Paul Groves co-stars alongside Graham and Domingo, taking the role of Pylade, and baritone William Shimell sings King Thoas in a production described by the Seattle Post-Intelligencer as a "rare treasure" and by The Seattle Times as "a theatrical marvel" when it ran at Seattle Opera earlier this fall.

The version of Iphigenie used by the Met for this production is something of a hybrid, adapted for the particular strengths of this cast. The bulk of the score will be performed in the original version Gluck wrote for Paris in 1779, but with some changes taken from the adaptation the composer made for its 1781 Vienna premiere, in which Oreste is a tenor rather than a baritone role. Other borrowings from the Vienna version include the transposed version of King Thoas's opera and several orchestral movements.

This evening's gala, beginning at 8:30 p.m. will be presented in free streaming audio at the Metropolitan Opera website, www.metopera.org, and will be broadcast live on Sirius Satellite Radio. The December 8 matinee will launch the new season of live Saturday afternoon broadcasts over the Toll Brothers-Metropolitan Opera International Radio Network. Iphigenie en Tauride runs for a total of eight performances at the Metropolitan Opera House through December 22.

By Matthew Westphal