In 1915 he was hired as musical director for the New York Hippodrome after the previous music director, Manuel Klein, left abruptly after a disagreement with Lee Shubert and Jacob J. Shubert. Hubbell also wrote the score for "Good Times", which ran for 456 performances at the New York Hippodrome. He continued composing for the theater until 1923. The song he is most remembered for, "Poor Butterfly", was written for one of the first shows he wrote for the Hippodrome, "The Big Show". According to his obituary, he thought his best song was "The Ladder of Roses", written for the 1915 Hippodrome hit, "Hip-Hip-Hooray".