This is the first New York production of the little-known “Orpheus,” composed in 1726, which came to attention when a manuscript was discovered in 1978. The work is no historical curiosity but a beguiling and innovative opera with an unabashedly eclectic score. Though simple, the modern-dress production by the director Rebecca Taichman, with sets and costumes by David Zinn, is at once fanciful and daring. Ms. Taichman draws nuanced and vulnerable performances from a young, attractive cast. Gary Thor Wedow conducts a lively chamber orchestra and also plays virginal in the continuo group of period instruments. Though the performance was exhilarating and the opera a revelation, what this production signals for the company’s future post-Lincoln Center is hard to say. Tickets are almost gone for the run. But if all four performances sell out, the total attendance will still not equal one sold-out night at the company’s former home, the renovated David H. Koch Theater in Lincoln Center. There will be time for the company and its supporters to grapple with these issues; for now there is a significant production of a Telemann opera to savor. And who knew? In some circles Telemann is unfairly considered a second-rank composer, though anyone who churned out more than 3,000 works, as Telemann is thought to have done, risks being seen as a production-line operator. While maintaining music directorships at the major churches in Hamburg, Germany, Telemann was also the music director of the Gänsemarkt theater, a position he held from 1722 until the opera house went out of business in 1738. There he presented important operas by other composers, especially Handel. Telemann may have written 50 operas, though only about 9 exist in complete scores. It is possible that “Orpheus” received only a concert performance in Hamburg. The anonymous libretto is based on a French play translated into German. Telemann also lifted bits of text from French and Italian operas he admired, incorporating the original words. The idea of a trilingual libretto may seem absurd. But in the best sense Telemann’s musical language is a fusion of German, French and Italian Baroque styles. The stylistic and linguistic shifts in “Orpheus” actually lend the opera variety and character. The score, performed here in two acts, is wondrously varied: no Handelian string of da capo arias but a natural flow from recitatives through arias of all shapes and sizes to duets and ensembles. What drives the drama and brings a startling twist to the legend of Orpheus and Eurydice is the dominant role of Orasia, the Queen of Thrace, who has an obsessive, unrequited love for Orpheus. When the opera opens, Orpheus and Eurydice have just wed. But Orasia commands the stage for the first 20 minutes, venting her frustration and fury. The soprano Jennifer Rowley holds nothing back in her scenery-chewing, vocally visceral portrayal of Orasia. Her big top notes may be strident, but she inhabits the role, attacks the fiery coloratura passagework and sends steely phrases flying. From the large, efficient handbag that her attendant Ismene carries, Orasia takes a compact mirror and eye makeup to primp herself before trying again to woo Orpheus. The soprano Michelle Areyzaga sang Ismene in the first half but withdrew because of illness and was replaced in the second part by the winning Joanna Ruszala. (Evidently the downsized company’s artistic team had dependable cover singers ready to go.)