Vernon's first Ko-Ko in "The Mikado" was in Williamson's 1885 production. He played Sir Marmaduke in the company's "The Sorcerer" in 1886 and King Hildebrand in "Princess Ida" in 1887. "The Otago Daily Times" wrote in 1887 of his Ko-Ko that he "specially shines in his treatment of those lyrics which depend much upon enunciation and bye-play for their effect." He also finally played the Lord Chancellor in "Iolanthe" in 1887. The same paper commented, "Nothing could be more refinedly humorous than Mr Vernon's Lord Chancellor. ... His conscientious gravity was alternated ... with a wild friskiness that would have appalled Chancery Lane. His excruciating glance supplied "the" funny element in the trio 'If you go in'."