Sylvester O'Halloran (1728 - 1807) was a renowned surgeon with an abiding interest in Gaelic poetry and history. For most of his life he lived and practised in Limerick. With a tall slender figure attired in French costume, and with an impressive wig, cocked hat, and gold-headed cane, O'Halloran cut quite a dash around town and participated actively in the social life of Limerick city. He was very committed to education, research and surgical skills. In 1765 he proposed a College of Surgeons along the lines of the College de St. Cosme in Paris. His proposal led to the founding of the Royal College of Surgeons in Ireland. Combining careful research with the principles of fiction writing, Insula Sacra by Jack Hogan ethically tells a fact-based story of the life and work of Sylvester O'Halloran. Using the storytelling techniques of fiction, Jack Hogan imagined his way back into the late 1700s in Limerick city, recreating the ideas and words of Sylvester O'Halloran and his contemporaries.