Join the Tufts Opera Ensemble for two mystical and mysterious one-act operas: “The Medium” by Gian Carlo Menotti and “A Game of Chance” by Seymour Barab. Carol Mastrodomenico, stage director; Thomas Stumpf, music director. Free to the public with no tickets required; also viewable via Tufts Music Live Streaming. The program will be repeated at 8 p.m. on Friday, April 26, in Distler Hall.