At age 25, Beethoven carefully chose his first published work, Opus 1, a set of three lively piano trios that reveal the influence of his onetime teacher Franz Joseph Haydn. He employed the format only sporadically after turning 30, yet his later trios—including his final two, published in 1809 as Opus 70—include his mysterious, unsettling Ghost Trio, which is as indelible, dramatic, and magnificently scaled as any of its predecessors.