The countertenor Anthony Roth Costanzo, fresh from his triumph in the Metropolitan Opera’s recent production of Akhnaten, where he entered nude and was soon clothed in gold, now takes the stage as a water nymph—Galatea—in this acclaimed production of Handel’s serenata Aci, Galatea e Polifemo. It’s a mythological tale that Handel took through a number of iterations, but this is the first, premiered in 1708, and much less familiar than the later English-language Acis and Galatea. The soprano Lauren Snouffer is cast as the mortal shepherd Aci, and bass-baritone Davóne Tines is the cyclops Polifemo. —L.J.