As the finale to its current season, NIU Opera Theater, in collaboration with the NIU Philharmonic, presents Carlo Menotti’s first English opera, “The Old Maid and the Thief.” Performances are at 7:30 p.m. Friday, April 1, and 3 p.m. Sunday, April 3, in Boutell Memorial Concert Hall, located at 400 Lucinda Ave. in the NIU Music Building. “The...