If John Martyn Harlow is known at all in the neurosciences, it is because he was the physician who attended Phineas Gage and followed up his case. Although Harlow's brief but insightful accounts of the changes in Gage's personality are fairly well recognized, and his skill in treating Gage often acknowledged, Harlow himself is, for the most part, the shadowy figure caught by the self-depreciatory characterization of the subtitle of this paper. Although his contribution to the neurosciences was singular, literally and figuratively, he deserves a place in the history of the subject. Harlow's training in antiphlogistic therapy can be seen in his treatment of Gage and in his evaluation of its results. As a medical student, he was also exposed to phrenological doctrine, the influence of which can also be seen in his appreciation and explanation of some aspects of Gage's behaviour. Manuscript materials, newspaper reports, and other little known material are used here to evaluate Harlow's contributions to medicine and to the medical, political, and civic life of Cavendish, Woburn, and the Commonwealth of Massachusetts.