Sullivan created the role of Apollo in his brother's first operatic collaboration with W. S. Gilbert, "Thespis", at the Gaiety Theatre, which ran from December 1871 until March 1872. During this run, he also starred in the companion pieces "Dearer than Life" by H. J. Byron and "Ganymede and Galatea", among other works. He continued to appear at the Gaiety Theatre in 1872 and 1873, playing Patachon in Jacques Offenbach's "Les deux aveugles" (1872) and in "The Magic Fife", a translation of another Offenbach operetta (1873). He moved to the Holborn Empire Theatre by early 1874.