With its plot poised on a knife edge between comedy and drama, Xerxes is among the most engaging of Handel’s operas. The action begins with music often heard on church organs as “Handel’s Largo,” here a love song to a tree sung by the eponymous king of Persia. This time, the role goes to Key’mon Murrah, a Black countertenor whose timbre bears an uncanny resemblance to that of the late, great Black soprano Jessye Norman. The production is by Tazewell Thompson, whose voluptuous stage imagery has played to acclaim at the chic summertime Glimmerglass Festival in upstate New York. Jane Glover conducts. —Matthew Gurewitsch