A burlesque of the popular British comic opera H. M. S. Pinafore, or, The Lass that Loved a Sailor (1878), Kelly and Leon's version was advertised as having been specially adapted, localised, and 'paraphrased from Gilbert and Sullivan' by permission of J. C. Williamson's. Among the local allusions and topicalities targeted were the Exhibition and members of the Victorian parliament.
H. M. S. Pin-A-4 may also have been derived in part from an American Pinafore minstrel burlesque that had been staged in Australia earlier.
Kelly and Leon appear to have staged the production in order to take advantage of public interest in the action brought by Gilbert and Sullivan against actor/manager W. H. Lingard, who had produced the original comic opera at Melbourne's Academy of Music earlier in the year. The decision against Lingard was reached the day before Kelly and Leon debuted their production.
1880: St George's Hall, Melbourne, 30 October - 19 November.