Music, madness, murder and Mozart are the themes of Peter Shaffer’s “Amadeus,” now on stage at Warren’s 2nd Story Theatre. The story, which centers on the fictionalized lives of composers Wolfgang Amadeus Mozart and Antonio Salieri, includes the music of both, in addition to that of other composers from the same time period. According to 2nd Story, the production “weaves a confrontation between mediocrity and genius into a tale of breathtaking dramatic power.” “Amadeus” will run through Sunday, Feb. 24.