Mezzo-soprano Joyce DiDonato leads as the imperious title empress in the Met’s first-ever performance of this tale of deception and deceit. Set in Ancient Rome, Agrippina plots the downfall of Emperor Claudius to secure the throne for her son Nero, in Handel’s first operatic triumph. Harry Bicket conducts Sir David McVicar’s wry new production, which gives this Baroque black comedy a politically charged, modern updating.