Un Ballo in Maschera centers on the assassination of King Gustavus III of Sweden, who was killed at a masked ball in Stockholm in 1792. Verdi’s opera suffered interference from censors (including the King of Naples), who objected to a royal assassination being portrayed on stage. Adapted settings for past productions of the opera have included everything from 17th-century Boston to 19th century Naples. The Met’s current production returns the action to its original Swedish setting, as it explores the intersection of the public and private lives of those in power.