The deadly, tumultuous Rome of 1800 is back onstage at Covent Garden in Jonathan Kent’s production of Puccini’s Tosca, created for the Royal Opera in 2006. The mood of temptation and sexual betrayal is rendered superbly by Paul Brown’s set designs, and the threat of Napoleon’s invasion provides a dramatic backdrop. Tosca is based on the French play La Tosca, written by Victorien Sardou in 1887. The work runs high on melodrama, and low on characters left standing at its conclusion. Angela Gheorghiu sings the title role. —Rebecca Dolan